This document provides information about the June 2004 Biology exam for the Cambridge O Level qualification. It includes the following:
1) Details of the multiple choice (Paper 1) and core and extended papers (Papers 2 and 3), including the number and types of questions.
2) Summaries of candidate performance on specific multiple choice questions, identifying common misconceptions or areas of difficulty.
3) Comments on candidate responses to questions on Papers 2 and 3, noting both strengths and weaknesses in understanding of various biology concepts assessed.
Scientists at the National Cancer Institute developed an automated assay that uses fluorescent markers and mammalian cells to detect biologically active steroidal endocrine-disrupting chemicals (EDCs) in water samples. Testing of water samples from 14 states found androgen activity in 35% and previously unrecognized glucocorticoid activity in 27%. The assay is more efficient than chemical analysis at determining biological activity and is suitable for wide application in testing water samples.
1. The document describes a system designed to meet the basic needs of a family of four living in the tropics. The system generates fuel gas from bacterial fermentation of urine and feces. It uses solid waste from the fermenter as fertilizer for crops and stocks the pond with fish that feed on algae rather than carnivorous fish.
2. The document discusses student responses to questions about the nitrogen cycle and leguminous plants. It notes confusion between nitrogen fixing and denitrifying bacteria. It also notes that students have difficulty with the sequence of changes in the nitrogen cycle and defining nitrogen compounds.
3. The document evaluates student essays on relationships between animals and plants. It finds the scientific
This document provides a summary of Fengkun Du's career and qualifications. It outlines his experience as a microbiologist with over 7 years working in proteomic research and the wastewater industry. It also details his education including a PhD in Applied and Environmental Microbiology from Georgia State University and collaborations with various universities. His skills include protein purification techniques, cell culture, fermentation, microarray data analysis and more.
This document discusses antibiotic resistance (ABR) in agricultural systems. It notes that while most public attention has focused on ABR in healthcare settings, comparatively little research has examined environmental sources of ABR from soil and water bacteria. The document summarizes several studies that have investigated ABR levels in agricultural soils amended with manure or wastewater, finding increased ABR genes but with levels returning to baseline over time. It also discusses challenges in standardizing methods for measuring ABR and the complex relationship between agricultural practices and observed ABR levels.
Wagner College Forum for Undergraduate Research, Vol. 15 No. 1Wagner College
This document provides an introduction and summaries of papers presented in the Wagner Forum for Undergraduate Research journal. It discusses the purpose of the journal in publishing student research and outlines the sections and types of papers included. Abstracts are provided for 10 studies presented at the Eastern Colleges Science Conference on topics ranging from bacterial infections in zebrafish to the effects of plant extracts on bacteria. Full papers are summarized on detecting proteins in flatworm genomes and the benefits of diversity in corporate management.
Wagner College Forum for Undergraduate Research, Vol. 17 No. 1Wagner College
The Fall 2018 issue contains abstracts by Kevin Lipton, John Acquaviva, Lejla Bolevic, Anna Cios, Lauren Taibi, Samantha Susi & Jack Leighton, Mara Mineo, Tamar Amirov & Vinh Phuong, Kelsey Savje & Domenick Palmieri, Oskar Sundberg & Iireyel Gittens, Ellen Reidy, Derek Avery, Zachary Pandorf & Michelle Hernandez, Piper Skinner, Matthew Barreto & Victor Ruan, Monica Valero and Gent Prelvukaj. It also contains articles by Adam O’Brien, Cathryn Cantyne, Claire Johnson & Jacqueline Otake, Jordan Gonzales, Jacquelyn Thorsen, John Badagliacca, Elena Rotzokou, Ethan Meyer and Glen MacDonald.
BIO 240 TUTORIAL Education Planning--bio240tutorial.comkopiko234
FOR MORE CLASSES VISIT
www.bio240tutorial.com
how forensic scientists take advantage of genomic variations in noncoding regions of DNA • the techniques of polymerase chain reaction (PCR) and gel electrophoresis Introduction
This document consists of a 40 multiple choice question biology exam with four possible answers for each question. The exam covers topics including characteristics of living organisms, plant and animal cell structure, transport processes, photosynthesis, respiration, circulation, excretion, genetics, ecology, and environmental pollution. It provides high level information to test understanding of essential biology concepts.
Scientists at the National Cancer Institute developed an automated assay that uses fluorescent markers and mammalian cells to detect biologically active steroidal endocrine-disrupting chemicals (EDCs) in water samples. Testing of water samples from 14 states found androgen activity in 35% and previously unrecognized glucocorticoid activity in 27%. The assay is more efficient than chemical analysis at determining biological activity and is suitable for wide application in testing water samples.
1. The document describes a system designed to meet the basic needs of a family of four living in the tropics. The system generates fuel gas from bacterial fermentation of urine and feces. It uses solid waste from the fermenter as fertilizer for crops and stocks the pond with fish that feed on algae rather than carnivorous fish.
2. The document discusses student responses to questions about the nitrogen cycle and leguminous plants. It notes confusion between nitrogen fixing and denitrifying bacteria. It also notes that students have difficulty with the sequence of changes in the nitrogen cycle and defining nitrogen compounds.
3. The document evaluates student essays on relationships between animals and plants. It finds the scientific
This document provides a summary of Fengkun Du's career and qualifications. It outlines his experience as a microbiologist with over 7 years working in proteomic research and the wastewater industry. It also details his education including a PhD in Applied and Environmental Microbiology from Georgia State University and collaborations with various universities. His skills include protein purification techniques, cell culture, fermentation, microarray data analysis and more.
This document discusses antibiotic resistance (ABR) in agricultural systems. It notes that while most public attention has focused on ABR in healthcare settings, comparatively little research has examined environmental sources of ABR from soil and water bacteria. The document summarizes several studies that have investigated ABR levels in agricultural soils amended with manure or wastewater, finding increased ABR genes but with levels returning to baseline over time. It also discusses challenges in standardizing methods for measuring ABR and the complex relationship between agricultural practices and observed ABR levels.
Wagner College Forum for Undergraduate Research, Vol. 15 No. 1Wagner College
This document provides an introduction and summaries of papers presented in the Wagner Forum for Undergraduate Research journal. It discusses the purpose of the journal in publishing student research and outlines the sections and types of papers included. Abstracts are provided for 10 studies presented at the Eastern Colleges Science Conference on topics ranging from bacterial infections in zebrafish to the effects of plant extracts on bacteria. Full papers are summarized on detecting proteins in flatworm genomes and the benefits of diversity in corporate management.
Wagner College Forum for Undergraduate Research, Vol. 17 No. 1Wagner College
The Fall 2018 issue contains abstracts by Kevin Lipton, John Acquaviva, Lejla Bolevic, Anna Cios, Lauren Taibi, Samantha Susi & Jack Leighton, Mara Mineo, Tamar Amirov & Vinh Phuong, Kelsey Savje & Domenick Palmieri, Oskar Sundberg & Iireyel Gittens, Ellen Reidy, Derek Avery, Zachary Pandorf & Michelle Hernandez, Piper Skinner, Matthew Barreto & Victor Ruan, Monica Valero and Gent Prelvukaj. It also contains articles by Adam O’Brien, Cathryn Cantyne, Claire Johnson & Jacqueline Otake, Jordan Gonzales, Jacquelyn Thorsen, John Badagliacca, Elena Rotzokou, Ethan Meyer and Glen MacDonald.
BIO 240 TUTORIAL Education Planning--bio240tutorial.comkopiko234
FOR MORE CLASSES VISIT
www.bio240tutorial.com
how forensic scientists take advantage of genomic variations in noncoding regions of DNA • the techniques of polymerase chain reaction (PCR) and gel electrophoresis Introduction
This document consists of a 40 multiple choice question biology exam with four possible answers for each question. The exam covers topics including characteristics of living organisms, plant and animal cell structure, transport processes, photosynthesis, respiration, circulation, excretion, genetics, ecology, and environmental pollution. It provides high level information to test understanding of essential biology concepts.
This document consists of a biology exam with 40 multiple choice questions testing various concepts related to biology. The exam is 45 minutes long and students are instructed to choose the correct answer for each question and record their choice on an answer sheet provided. The document provides context, diagrams, tables, graphs and photographs to aid understanding of the questions.
This document contains instructions for a 1-hour biology exam. It details 4 sections containing multiple choice and written response questions that assess students' understanding of topics like plant and animal cell structure and function, enzymes, and human health. Students are to record their answers on the question paper. The exam document provides guidance on marking, materials allowed, and copyright information.
This document consists of an exam for the International General Certificate of Secondary Education in Chemistry. The exam contains 7 questions testing knowledge of chemistry experiments and concepts. Students are asked to interpret diagrams of apparatus, complete tables of results, draw graphs, identify substances, explain observations, and plan an experimental procedure.
This document consists of a biology exam with multiple choice questions testing knowledge of various biology concepts. It includes 15 printed pages of questions about topics like cell structure, plant and animal biology, digestion, circulation, gas exchange, excretion, nervous coordination, reproduction, genetics, ecology and environmental pollution. The questions are in a multiple choice format with 4 possible answers for each question.
This document contains an exam for the International General Certificate of Secondary Education (IGCSE) Biology exam. The exam consists of 3 sections with multiple choice and free response questions about biology topics. Section 1 involves an experiment on heat transfer and insulation. Students are asked to analyze data from the experiment, explain the results, and evaluate the experimental design. Section 2 compares the internal structures of tomatoes and apples under a microscope. Section 3 examines the germination of pollen grains and growth of pollen tubes. Students are asked to identify structures, make measurements, and do calculations related to these topics.
This document is an 8 page biology exam paper from October/November 2004 consisting of 4 sections with multiple choice and structured questions. The questions cover topics such as:
1) Comparing the external features and calculating the sizes of two different types of worms.
2) Analyzing data on blackspot fungus infections on rose leaves from polluted and non-polluted areas.
3) Explaining the color change that occurs when apples are cut and the effect of pH on this change.
4) Identifying structures in leaf diagrams including veins, leaflets, cell layers and chloroplast-containing cells.
This document is a biology exam for the International General Certificate of Secondary Education. It consists of 40 multiple choice questions testing students' knowledge of various biology topics. The exam covers areas like cell biology, transport systems, ecology, genetics, and human biology. Students must choose the single best answer for each question from the four options given and record their choices on a separate answer sheet.
This document consists of 19 printed pages summarizing an International General Certificate of Secondary Education Biology exam from May/June 2013. The exam contains 6 sections with multiple choice and written response questions covering topics such as human anatomy, ecosystems, plant transport, enzyme function, bacterial growth, and evolution. Students are asked to label diagrams, define terms, describe processes, and explain experimental results. The exam is designed to test students' understanding of core biology concepts.
This document contains mark schemes for Chemistry examinations from June 2004, including:
- The mark scheme and maximum marks for multiple choice, core, and extended papers.
- Details on how examiners were instructed to award marks and handle unexpected responses.
- Grade thresholds for each exam component.
- Sample exam questions and answers with marks allocated.
This document provides an overview of topics related to cell biology, including:
- An introduction to cells that describes the cell theory and differences between prokaryotic and eukaryotic cells. Specialization of cells allows for differentiation and development of multicellular organisms.
- Ultrastructure of cells, describing that eukaryotes have more complex structures than prokaryotes due to compartmentalization of organelles. Electron microscopes revealed greater details of cellular structures.
- Membrane structure, explaining that phospholipid bilayers form fluid biological membranes allowing for dynamic transport of materials. The fluid mosaic model describes current understanding of membrane structure.
A work in progress - drafts to be updated and completed later. Practice with the the assessment statements from the Core component of the course that require diagrams.
1. Most candidates understood how species conservation could result from selective logging but had difficulty clearly expressing these ideas. Some incorrectly imagined minerals redistributing over long distances from unlogged to logged areas. Most recognized the importance of sufficient time for tree regrowth.
2. Many candidates confused fertilizers and pesticides. Most explained ladybird consumption of greenflies accumulating insecticide but some incorrectly suggested insecticide increasing from greenfly reproduction. Patterns of population changes were often described poorly.
3. Candidates correctly identified interspecific competition but had difficulty calculating growth rate differences between spruce and heather in a control experiment.
1. The document describes a system designed to meet the basic needs of a family of four living in the tropics. The system generates fuel gas from bacterial fermentation of urine and feces. It uses solid waste from the fermenter as fertilizer and grows leguminous plants such as beans and peanuts. Fish that feed on algae are stocked in the pond rather than carnivorous fish.
2. Candidates were asked questions about various parts of the system. For example, how the nitrogen cycle makes nitrogen in urine and feces available to plants, the advantages of growing legumes, and the benefits of stocking the pond with algae-feeding fish rather than carnivorous fish.
This document contains summaries of exam responses on topics related to ecology and succession:
1) Many candidates incorrectly described industrial effluent or slurry spillage instead of the provided explanation of weathered rock for shoreline deposits. Few could apply knowledge of succession to explain climax communities.
2) Most calculated diversity indices correctly but responses varied in interpreting the results. Better responses recognized adaptations allowing Fucus spiralis to outcompete others in its habitat.
3) Some wrote too much about succession where not required, failing to distinguish key points about changes in species numbers and individuals. Most described pioneer species roles but some unnecessary detailed climax communities.
4) Many misinterpreted the provided graph and did
Investigación con embriones humanos ¿sí o noseminary
This document provides a summary of a book that discusses the findings from the examination of "Lindow Man", a well-preserved bog body discovered in 1984 in the UK. A multi-disciplinary team of 35 experts studied Lindow Man to learn about Iron Age people in northwest Europe. They found that Lindow Man was 168 cm tall, had type O blood, and had been killed through garotting and stabbing. Carbon dating of the body provided conflicting dates between 100 AD and 400 AD. The examination provided new insights into the lives and deaths of people from that time period.
This document provides a report on the performance of candidates who took the Caribbean Examinations Council Secondary Education Certificate Examinations in Integrated Science in June 2004. It summarizes the results at both the basic and general proficiency levels. At the general proficiency level, there was a slight increase in enrollment and performance was satisfactory, with more candidates achieving grades I to III compared to the previous year. At the basic proficiency level, enrollment and performance decreased compared to the previous year, with fewer candidates achieving the top grades. The report then provides detailed comments on candidate performance on each exam paper.
- The Second Amendment protects the right of individuals to keep and bear arms, while the Fifth Amendment protects individuals from self-incrimination and being deprived of life, liberty or property without due process of law.
- Both amendments aim to limit government overreach and protect individual rights and freedoms by restricting the powers of the government.
- The Bill of Rights, including the Second and Fifth Amendments, was implemented in response to concerns from Anti-Federalists that the new Constitution did not adequately protect individual liberties from government overreach.
1. One condition that seems to lead to senescence and not apoptosi.docxjackiewalcutt
1. One condition that seems to lead to senescence and not apoptosis in stem cells is
a. shortening of telomeres below a critical limit
b. base damage to DNA
c. unequal division of chromosomes at anaphase
d. none of the above
2. Knowing that even in the oldest people's stem cells seem to have many cell divisions left to them when cultured in vitro (in a dish), the you might contend that a possible reason for that was
a. Absence of inhibitory factors found in the old bodies in the new culture medium
b. factors in the cellular environment of old people's bodies
c.
The presence of high levels of growth factors in the culture serum
d. All of the above
3. In 1962, Leonard Hayflick conducted an experiment that supported Weismann's Theory of programmed death. He proposed The Hayflick Limit which can be reached faster by:
a. Increasing the rate of cell division
b. Underfeeding cells
c. Decreasing the rate of mutations
d. Synthetically elongating telomeres.
4. The antagonistic pleiotropy theory of aging assumes that each gene has only one effect on the phenotype of an organism at different stages of its life. True or False
5. In Conboy's study on heterochronic parabiotic pairs, which phrase described what future studies should focus on according to the results of this study?
a. adult stem cells
b. changes in aging cells
c. muscle cell regeneration
d. changes in aging plasma
6.- 7. Briefly explain what happened to old stem and progenitor cells in a young systemic environment.
8. Which substance is the most common in cells?
a. carbohydrates
b. salts and minerals
c. proteins
d. fats
e. water
9.
- 11. Describe how an enzyme may change the transcription patterns of a cell by adding chemical groups to histone proteins. What is this called?
12. Acetyl L-Carnitine/Alpha lipoic acid are ____________ that are produced naturally by the body in _______
a. Amino acids, large amounts
b. Antioxidants, small amounts
c. Toxins, abundance
d. ROS, trace amounts
13. Most genes that determine lifespan in C. elegans are directly in DNA repair. True or False
14.- 16. What is the preferable study group in mammalian testing of aging interventions Mice or monkeys? Why?
17 - 19. If you were to run a retirement community what would you do to improve the health/lives of the people who depend on you?
20. The ____________ ____________ theory , states that there exists a biological clock and a time dependent plan or program that directs a limitation to a lifespan?
a. DNA damage
b. Evolveabity Theory
c. Mutation-accumulation
d. free radical
21. - 24. Unlike inorganic objects like rocks or even computers (at present) , living organisms can repair damage or rebuild or even recycle damages at the sub-cellular level. Give three
instances cellular systems involved in repairing cellular damages.
25. . An often given example ...
The document discusses genetic engineering in agriculture. It provides background on genetic engineering and its history. Common genetically engineered crops are discussed, as well as traits modified like herbicide tolerance. Both proponents and opponents of genetic engineering are mentioned. Regulatory bodies that oversee genetically engineered products are identified. Controversies around intellectual property and corporate influence on policy are also summarized. Alternatives to genetic engineering are briefly explored.
The document discusses genetic engineering in agriculture. It provides background on genetic engineering and its history. Common genetically engineered crops are mentioned, as well as traits modified like herbicide tolerance. Both proponents and opponents of genetic engineering are discussed. Regulations around genetically engineered products are explored, as are issues around intellectual property. Alternatives to genetic engineering in agriculture are also presented.
The document discusses genetic engineering in agriculture. It provides background on genetic engineering and its history. Common genetically engineered crops are mentioned, as well as traits modified like herbicide tolerance. Both proponents and opponents of genetic engineering are discussed. Regulations around genetically engineered products are explored, as are issues around intellectual property. Alternatives to genetic engineering in agriculture are also presented.
The document describes the synthesis and characterization of a manganese catalyst with the ligand BPMP (bis(2-pyridylmethyl)piperazine) for alcohol oxidation reactions. The BPMP ligand was synthesized according to a published procedure and then reacted with manganese(II) triflate to form the complex [Mn(BPMP)(OTf)2]. X-ray crystallography showed the manganese atom had a distorted trigonal prismatic coordination geometry. Testing showed the heterogeneous catalyst could efficiently oxidize various benzylic alcohols and cinnamyl alcohol to the corresponding aldehydes without over-oxidation.
This document consists of a biology exam with 40 multiple choice questions testing various concepts related to biology. The exam is 45 minutes long and students are instructed to choose the correct answer for each question and record their choice on an answer sheet provided. The document provides context, diagrams, tables, graphs and photographs to aid understanding of the questions.
This document contains instructions for a 1-hour biology exam. It details 4 sections containing multiple choice and written response questions that assess students' understanding of topics like plant and animal cell structure and function, enzymes, and human health. Students are to record their answers on the question paper. The exam document provides guidance on marking, materials allowed, and copyright information.
This document consists of an exam for the International General Certificate of Secondary Education in Chemistry. The exam contains 7 questions testing knowledge of chemistry experiments and concepts. Students are asked to interpret diagrams of apparatus, complete tables of results, draw graphs, identify substances, explain observations, and plan an experimental procedure.
This document consists of a biology exam with multiple choice questions testing knowledge of various biology concepts. It includes 15 printed pages of questions about topics like cell structure, plant and animal biology, digestion, circulation, gas exchange, excretion, nervous coordination, reproduction, genetics, ecology and environmental pollution. The questions are in a multiple choice format with 4 possible answers for each question.
This document contains an exam for the International General Certificate of Secondary Education (IGCSE) Biology exam. The exam consists of 3 sections with multiple choice and free response questions about biology topics. Section 1 involves an experiment on heat transfer and insulation. Students are asked to analyze data from the experiment, explain the results, and evaluate the experimental design. Section 2 compares the internal structures of tomatoes and apples under a microscope. Section 3 examines the germination of pollen grains and growth of pollen tubes. Students are asked to identify structures, make measurements, and do calculations related to these topics.
This document is an 8 page biology exam paper from October/November 2004 consisting of 4 sections with multiple choice and structured questions. The questions cover topics such as:
1) Comparing the external features and calculating the sizes of two different types of worms.
2) Analyzing data on blackspot fungus infections on rose leaves from polluted and non-polluted areas.
3) Explaining the color change that occurs when apples are cut and the effect of pH on this change.
4) Identifying structures in leaf diagrams including veins, leaflets, cell layers and chloroplast-containing cells.
This document is a biology exam for the International General Certificate of Secondary Education. It consists of 40 multiple choice questions testing students' knowledge of various biology topics. The exam covers areas like cell biology, transport systems, ecology, genetics, and human biology. Students must choose the single best answer for each question from the four options given and record their choices on a separate answer sheet.
This document consists of 19 printed pages summarizing an International General Certificate of Secondary Education Biology exam from May/June 2013. The exam contains 6 sections with multiple choice and written response questions covering topics such as human anatomy, ecosystems, plant transport, enzyme function, bacterial growth, and evolution. Students are asked to label diagrams, define terms, describe processes, and explain experimental results. The exam is designed to test students' understanding of core biology concepts.
This document contains mark schemes for Chemistry examinations from June 2004, including:
- The mark scheme and maximum marks for multiple choice, core, and extended papers.
- Details on how examiners were instructed to award marks and handle unexpected responses.
- Grade thresholds for each exam component.
- Sample exam questions and answers with marks allocated.
This document provides an overview of topics related to cell biology, including:
- An introduction to cells that describes the cell theory and differences between prokaryotic and eukaryotic cells. Specialization of cells allows for differentiation and development of multicellular organisms.
- Ultrastructure of cells, describing that eukaryotes have more complex structures than prokaryotes due to compartmentalization of organelles. Electron microscopes revealed greater details of cellular structures.
- Membrane structure, explaining that phospholipid bilayers form fluid biological membranes allowing for dynamic transport of materials. The fluid mosaic model describes current understanding of membrane structure.
A work in progress - drafts to be updated and completed later. Practice with the the assessment statements from the Core component of the course that require diagrams.
1. Most candidates understood how species conservation could result from selective logging but had difficulty clearly expressing these ideas. Some incorrectly imagined minerals redistributing over long distances from unlogged to logged areas. Most recognized the importance of sufficient time for tree regrowth.
2. Many candidates confused fertilizers and pesticides. Most explained ladybird consumption of greenflies accumulating insecticide but some incorrectly suggested insecticide increasing from greenfly reproduction. Patterns of population changes were often described poorly.
3. Candidates correctly identified interspecific competition but had difficulty calculating growth rate differences between spruce and heather in a control experiment.
1. The document describes a system designed to meet the basic needs of a family of four living in the tropics. The system generates fuel gas from bacterial fermentation of urine and feces. It uses solid waste from the fermenter as fertilizer and grows leguminous plants such as beans and peanuts. Fish that feed on algae are stocked in the pond rather than carnivorous fish.
2. Candidates were asked questions about various parts of the system. For example, how the nitrogen cycle makes nitrogen in urine and feces available to plants, the advantages of growing legumes, and the benefits of stocking the pond with algae-feeding fish rather than carnivorous fish.
This document contains summaries of exam responses on topics related to ecology and succession:
1) Many candidates incorrectly described industrial effluent or slurry spillage instead of the provided explanation of weathered rock for shoreline deposits. Few could apply knowledge of succession to explain climax communities.
2) Most calculated diversity indices correctly but responses varied in interpreting the results. Better responses recognized adaptations allowing Fucus spiralis to outcompete others in its habitat.
3) Some wrote too much about succession where not required, failing to distinguish key points about changes in species numbers and individuals. Most described pioneer species roles but some unnecessary detailed climax communities.
4) Many misinterpreted the provided graph and did
Investigación con embriones humanos ¿sí o noseminary
This document provides a summary of a book that discusses the findings from the examination of "Lindow Man", a well-preserved bog body discovered in 1984 in the UK. A multi-disciplinary team of 35 experts studied Lindow Man to learn about Iron Age people in northwest Europe. They found that Lindow Man was 168 cm tall, had type O blood, and had been killed through garotting and stabbing. Carbon dating of the body provided conflicting dates between 100 AD and 400 AD. The examination provided new insights into the lives and deaths of people from that time period.
This document provides a report on the performance of candidates who took the Caribbean Examinations Council Secondary Education Certificate Examinations in Integrated Science in June 2004. It summarizes the results at both the basic and general proficiency levels. At the general proficiency level, there was a slight increase in enrollment and performance was satisfactory, with more candidates achieving grades I to III compared to the previous year. At the basic proficiency level, enrollment and performance decreased compared to the previous year, with fewer candidates achieving the top grades. The report then provides detailed comments on candidate performance on each exam paper.
- The Second Amendment protects the right of individuals to keep and bear arms, while the Fifth Amendment protects individuals from self-incrimination and being deprived of life, liberty or property without due process of law.
- Both amendments aim to limit government overreach and protect individual rights and freedoms by restricting the powers of the government.
- The Bill of Rights, including the Second and Fifth Amendments, was implemented in response to concerns from Anti-Federalists that the new Constitution did not adequately protect individual liberties from government overreach.
1. One condition that seems to lead to senescence and not apoptosi.docxjackiewalcutt
1. One condition that seems to lead to senescence and not apoptosis in stem cells is
a. shortening of telomeres below a critical limit
b. base damage to DNA
c. unequal division of chromosomes at anaphase
d. none of the above
2. Knowing that even in the oldest people's stem cells seem to have many cell divisions left to them when cultured in vitro (in a dish), the you might contend that a possible reason for that was
a. Absence of inhibitory factors found in the old bodies in the new culture medium
b. factors in the cellular environment of old people's bodies
c.
The presence of high levels of growth factors in the culture serum
d. All of the above
3. In 1962, Leonard Hayflick conducted an experiment that supported Weismann's Theory of programmed death. He proposed The Hayflick Limit which can be reached faster by:
a. Increasing the rate of cell division
b. Underfeeding cells
c. Decreasing the rate of mutations
d. Synthetically elongating telomeres.
4. The antagonistic pleiotropy theory of aging assumes that each gene has only one effect on the phenotype of an organism at different stages of its life. True or False
5. In Conboy's study on heterochronic parabiotic pairs, which phrase described what future studies should focus on according to the results of this study?
a. adult stem cells
b. changes in aging cells
c. muscle cell regeneration
d. changes in aging plasma
6.- 7. Briefly explain what happened to old stem and progenitor cells in a young systemic environment.
8. Which substance is the most common in cells?
a. carbohydrates
b. salts and minerals
c. proteins
d. fats
e. water
9.
- 11. Describe how an enzyme may change the transcription patterns of a cell by adding chemical groups to histone proteins. What is this called?
12. Acetyl L-Carnitine/Alpha lipoic acid are ____________ that are produced naturally by the body in _______
a. Amino acids, large amounts
b. Antioxidants, small amounts
c. Toxins, abundance
d. ROS, trace amounts
13. Most genes that determine lifespan in C. elegans are directly in DNA repair. True or False
14.- 16. What is the preferable study group in mammalian testing of aging interventions Mice or monkeys? Why?
17 - 19. If you were to run a retirement community what would you do to improve the health/lives of the people who depend on you?
20. The ____________ ____________ theory , states that there exists a biological clock and a time dependent plan or program that directs a limitation to a lifespan?
a. DNA damage
b. Evolveabity Theory
c. Mutation-accumulation
d. free radical
21. - 24. Unlike inorganic objects like rocks or even computers (at present) , living organisms can repair damage or rebuild or even recycle damages at the sub-cellular level. Give three
instances cellular systems involved in repairing cellular damages.
25. . An often given example ...
The document discusses genetic engineering in agriculture. It provides background on genetic engineering and its history. Common genetically engineered crops are discussed, as well as traits modified like herbicide tolerance. Both proponents and opponents of genetic engineering are mentioned. Regulatory bodies that oversee genetically engineered products are identified. Controversies around intellectual property and corporate influence on policy are also summarized. Alternatives to genetic engineering are briefly explored.
The document discusses genetic engineering in agriculture. It provides background on genetic engineering and its history. Common genetically engineered crops are mentioned, as well as traits modified like herbicide tolerance. Both proponents and opponents of genetic engineering are discussed. Regulations around genetically engineered products are explored, as are issues around intellectual property. Alternatives to genetic engineering in agriculture are also presented.
The document discusses genetic engineering in agriculture. It provides background on genetic engineering and its history. Common genetically engineered crops are mentioned, as well as traits modified like herbicide tolerance. Both proponents and opponents of genetic engineering are discussed. Regulations around genetically engineered products are explored, as are issues around intellectual property. Alternatives to genetic engineering in agriculture are also presented.
The document describes the synthesis and characterization of a manganese catalyst with the ligand BPMP (bis(2-pyridylmethyl)piperazine) for alcohol oxidation reactions. The BPMP ligand was synthesized according to a published procedure and then reacted with manganese(II) triflate to form the complex [Mn(BPMP)(OTf)2]. X-ray crystallography showed the manganese atom had a distorted trigonal prismatic coordination geometry. Testing showed the heterogeneous catalyst could efficiently oxidize various benzylic alcohols and cinnamyl alcohol to the corresponding aldehydes without over-oxidation.
This document provides an overview of key concepts in biology. It discusses how biology is the study of life and how all living things derive energy from the sun, are composed of chemicals, and show organization at the cellular level. It also addresses how reproduction ensures the ongoing existence of species and how organisms maintain homeostasis.
BIOL 101 Comprehensive Final Exam – Essay Portion U.docxAASTHA76
BIOL 101
Comprehensive Final Exam – Essay Portion
University of Maryland University College
Directions: Please complete the AnswerSheet file electronically and submit it via Assignments by March 6th
at 11:59 PM ET. Save your AnswerSheet in the following format: “LastName FINAL” (e.g., SmithFINAL).
Sources: You may use any electronic or print source from BIOL 101. When appropriate, you may use the
internet to locate additional supporting evidence (look for questions requiring it). AS ALWAYS, BE SURE TO
CITE ANY EXTERNAL RESOURCES YOU USE NEXT TO THE APPROPRIATE QUESTION.
Note: you may not consult any “living” resource in or out of this class, so do not seek assistance from your
peers or any other person. All essays will be run through the anti-plagiarism website, TurnItIn.com, and any
plagiarized material will be given a zero.
This exam is worth 200 points or 20% of your total grade. This section of the exam is essay, which is worth
100 pts (or half of the total points for the final exam). The other half of the final exam is a series of multiple-
choice questions, which is a separate link in our LEO classroom. Read the directions carefully below—you
have some choice in the Essay section. If you have any questions, e-mail me.
SHORT ESSAY QUESTIONS:
Complete all three. Answers should not exceed 1-2 paragraphs for each question. Worth 10 points each.
1. A population of grasshoppers in the Kansas prairie has two color phenotypes, green and brown.
Typically, the prairie receives adequate water to maintain healthy, green grass. Assume a bird that
eats grasshoppers moves into the prairie. How will this affect natural selection of the grasshoppers?
How might this change in a drought year?
2. Using material from this class, support the following statement with at least five pieces of evidence: a
plant-based (or vegetarian) diet is good for your health and the planet. Be sure to cite any external
evidence you use.
3. DNA and RNA are similar yet distinct components of the cell. Describe three differences between
RNA and DNA with respect to their chemical composition and structure. Provide a detailed
description of each characteristic you chose in your response.
ESSAY QUESTIONS:
Pick FIVE to answer—ONE FROM EACH PAIR. Each answer should be approximately 3-4 paragraphs in
length—maximum. Worth 14 points each.
4. Molecules of life and Cells (PICK A OR B TO ANSWER)
A. Pick three animal organelles and compare each one to a department or feature in a grocery or
department store. In other words, the organelles in a cell are analogous to various machines
and/or features in a store.
B. List the four “large molecules of life.” Identify their composition and structure, and describe one
function they perform in the cell.
5. Combining Micro and Macro concepts (PICK A OR B TO ANSWER)
A. Water is crucial for life as we know it. One of the most important char ...
This document discusses the increasing recognition of microorganisms in groundwater systems and their impact. It notes that groundwater microbiology is a newly developing field, as groundwater was long considered sterile. Microorganisms are now known to influence groundwater chemistry and the performance of wells. The document outlines some of the functions of microorganisms in groundwater, such as degrading pollutants and impacting water quality. It emphasizes that more understanding is needed of microbial communities and activities in groundwater systems to effectively manage this important water resource.
Character Analysis Essay Guideline | Templates at allbusinesstemplates.com. Character Analysis Essay Examples | PDF | Huckleberry Finn | Adventures .... School essay: Character analysis essay. Character essay - JPCEnglish(RT).
Isolation of Novel Mycobacteriophages from Tropical Soils of Puerto Rico avargas11
The document contains data from soil samples collected in Puerto Rico by four students - Aida Vargas de Jesus, Danilo Trinidad Pérez Rivera, Lizbeth Perez Castro, and Javier M. Zavala Ayala - as part of the RISE Program in the Department of Biology led by Prof. Eneida Díaz Pérez and Prof. Michael Rubin. The document includes tables with the coordinates, descriptions, locations, and dates of 12 soil samples collected by Danilo Trinidad Pérez Rivera and 7 soil samples collected by Aida Vargas de Jesus.
Need for Shift from Hypothesis to Data Driven Approach in Fisheries Research-...CrimsonpublishersMCDA
Science is not changing every day, but our understanding. Through systematic research based on hypothesis, scientists give a lead towards possible truth. With more and more such hypothesis, we can go nearer to the truth. In all fields of research, it is customary to design research based on hypothesis. Scientists test their hypothesis using suitable test statistics and arrive at some conclusion. But the technical, economic feasibility and replicability of such results will decide the rate of its adoptability. The results of sample survey, hypothesis-based research may go wrong in many instances. Intricacies between parameters in a dynamic aquatic system are so complex. This leads us to conclude the results with certain assumptions and conditions. These conditions and assumptions limit the translation of knowledge into reality. When dealing with system level research, developing and under developed countries cannot afford to waste time and money on hypothesis. Due to the advancement information technology, huge data can be collected, processed which enabled better understanding of correlations between parameters and results can be predicted with precisely. If the research shifts from hypothesis to data driven approach, most of the results can directly applied in the intended field. The results of Data Driven Approach in Research (DDAR) will play vital role in designing developmental programs and policy making. DDAR also attracts funding support from industries and more technology will move to the field.
Cultivation-Dependent Analysis of Microorganisms Associated withAnthony Harrington
This thesis examines culturable microorganisms isolated from various hydraulic fracturing fluid samples. 16S rRNA gene sequencing was used to identify isolates at the genus level, which represented Proteobacteria, Firmicutes, Actinobacteria, and Bacteroidetes. Isolates demonstrated tolerance to a wide range of salinity, pH, and temperature conditions. Some isolates were able to utilize hydrocarbons as a sole carbon source and produce biosurfactants/bioemulsifiers. Isolates also showed resistance to common biocides used in fracturing fluids. The study provides insight into microorganisms present in hydraulic fracturing fluids and their potential to impact operations.
Pennings, S. C., and R. M. Callaway. 1992. Salt marsh plant zonation.pdfrupeshmehta151
Pennings, S. C., and R. M. Callaway. 1992. Salt marsh plant zonation: the relative importance of
competition and physical factors. Ecology 73:681–690.
Questions 1. What three factors did the authors investigate in this study?
2. Summarize the design used for the two Salicornia experiments. Describe the predictor
variables, including their treatment levels, response variables, and number of replicates used in
each experiment. Explain how randomization was incorporated into the study. Provide a visual
diagram of the experimental design.
3. The authors state that as marsh elevation increases, stress from flooding decreases, while
stress from salinity increases. Did their results support this assertion? Which figures (number and
letter) present the results for flooding (soil waterlogging) and salinity (soil water potential)?
4. The authors state that one potential problem with the transplant experiment is that
transplanting itself may have an adverse effect. Did transplanting affect mortality? If yes,
provide documentation from the paper. Did transplanting affect growth? If yes, provide
documentation from the paper.
5. What evidence (cite relevant figures—number and letter) supports the author’s contention that
competition with Salicornia limits Arthrocnemum in the high Salicornia zone? What evidence
(cite relevant figures—number and letter) supports their contention that competition with
Arthrocnemum limits Salicornia in the Arthrocnemum zone?
6. Do the authors support their contention that multiple factors, both physical stresses and
interspecific competition, influence the zonation patterns observed in the salt marsh?
Solution
1. Flooding, soil salinity and competition
2. Two experiments were performed to investigate the relative importance of biological factors in
Salicornia and Arthrocnemum zoneation. Growth rate and biomass in several marsh zones were
measured initially followed by the reciprocally transplanted both species. Mass of green portions,
total mass and final percent were the prdictor variables. Growth of the plants were also
monitored and this is comes under response variables. Totally 3 replicates were used.
3. The broader marsh zones are determined by Salicornia greater flooding tolerance and it
allowing exist low in the marsh as well as Arthrocnemum greater tolerance to high salinity.
Figure 6-8 indicated that growth and survival of Salicornia and they are affected by both soil
water potential and flooding. Waterlogging affects redox potential and also affects the
availability of nutrients in the soil.
4. Survival of transplants was lower than the Salicornia, because survival and growth are affected
due to transplantation.
5 Figure 7 and Figure 8. Both species, not grown well in transition zone even through flooding is
much reduced. It is mainly due to the high salinity of the transition zone soil
6. Field patterns are ususlly determined by two physical factors that operating in a combination
with interspecific competition..
QUESTION 1Which ecological niche described below possesses the gre.pdfeyevisioncare1
QUESTION 1
Which ecological niche described below possesses the greatest number of prokaryotic cells
(select one)?
A.
Oceanic and Terrestrial sub-surfaces
B.
In or on non-prokaryotic organisms (humans, animals and plants)
C.
Dry land
D.
Lakes, rivers and oceans
E.
Earth stratosphere
1 points Saved
QUESTION 2
Which organism was primarily responsible for oxygenation of the earth approximately 2 billion
years ago (select one)?
A.
cyanobacteria
B.
Wooly mammoths
C.
Green sulfur bacteria
D.
Thermophilic archaea
E.
algae
1 points Saved
QUESTION 3
The earliest microorganisms were likely restricted to deep ocean and sub-surface ecological
niches until which of the following (select one)?
A.
Ozone layer developed
B.
Aquatic life carried them to land
C.
Phototrophy evolved
D.
Chemolithotrophy developed
E.
The development of chemoorganotrophy
1 points Saved
QUESTION 4
Two tubes are inoculated from one test tube of a bacterial culture. The cultures are then
transferred every day for 2 months. All of the media and growth conditions are the same in every
tube. After 2 months of cultivation, the fitness and genotype frequencies of the populations in the
two tubes are compared. The fitness of the two cultures is the same, but the genotype frequencies
are very different in the two cultures. How is this possible?
A.
This result is not possible because different genotype frequencies would result in different
fitness levels under the same growth conditions.
B.
Genetic drift within the small populations in the test tubes resulted in different genotype
frequencies.
C.
It is highly unlikely that any bacterial culture could be maintained for 2 months
D.
Natural selection caused the evolution of different genotype frequencies within the separate test
tubes.
E.
Two months is not long enough for different fitness levels to evolve even if the genotype
frequencies change.
1 points Saved
QUESTION 5
If you allowed 20 identical parallel Listeria cultures to evolve for 20,000 generations under new
growth conditions with very little nitrogen, the parallel cultures would do which of the following
(select one)?
A.
Direct mutations to occur in nitrogen utilization and uptake genes in order to adapt rapidly to the
culture conditions
B.
Each parallel culture would accumulate different random mutations resulting in different
adaptations to use the nitrogen in the media.
C.
Evolve identical adaptations to use the nitrogen source provided in the media
D.
Not change or adapt significantly over this small number of generations
E.
Each culture would evolve to use arsenic in place of nitrogen
1 points Save Answer
QUESTION 6
Which of the following statements are correct about the early formation of life on earth (select all
that apply)?
A.
Lateral gene transfer is one plausible explanation as to why organisms in Archaea, Bacteria, and
Eukarya still share so many genes among such distinct domains.
B.
The domains of life arose as barriers between gene exchange evolved between organisms
C.
W.
Deserts are expanding across large parts of the world due to various human and environmental factors. Overgrazing of livestock and deforestation have degraded soils, reducing their ability to retain water. Climate change has exacerbated droughts in many regions, reducing rainfall and causing desertification. As deserts expand, they threaten the livelihoods of those living in increasingly arid lands and could contribute to conflicts if populations are forced to migrate. Understanding and addressing the root causes, such as sustainable land management practices and reducing greenhouse gas emissions, is essential to slow the spread of deserts.
This friendship is rare and special. The friends have laughed together, cried together, and helped each other through difficult times. They share secrets without shame and tell each other the truth, even when at fault. The thought of the friendship ending makes one sad, but they take comfort in their memories. Though distance may separate them, their close bond of friendship remains in their hearts.
This friendship is rare and special. The friends have laughed together, cried together, and helped each other through difficult times. They share secrets without shame and tell each other the truth, even when at fault. The thought of the friendship ending makes one sad, but they take comfort in their memories. Though distance may separate them, their close bond of friendship remains in their hearts.
This document contains the same URL, www.communication4all.co.uk, repeated six times without any other text or context. The URL www.communication4all.co.uk is mentioned six consecutive times in the document.
This document contains the same URL, www.communication4all.co.uk, repeated six times without any other text or context. The URL www.communication4all.co.uk is mentioned six consecutive times in the document.
This document is a 13-page exam for the International General Certificate of Secondary Education in Biology. It contains 7 multiple choice questions testing knowledge of topics including food webs, human nutrition, plant and animal physiology, environmental issues, and genetics. The exam is designed to be completed in 1 hour and 15 minutes by writing answers directly on the question paper, with no additional materials allowed.
This document provides instructions for candidates taking the International General Certificate of Secondary Education Biology exam. It specifies that candidates should write their identification information on all work, use blue or black pen or pencil for diagrams, not use staples or correction fluid, answer all questions, and fasten all work together at the end. The exam consists of 13 printed pages, 3 blank pages, and 6 questions testing knowledge of biology topics including tissues, classification of organisms, response and control systems in humans and plants, hormones and disease, and population ecology.
This document is a 16-page exam for the International General Certificate of Secondary Education in Chemistry. It contains 7 multi-part chemistry questions testing knowledge of topics including the periodic table, atmospheric pollutants, acid-base reactions, extraction of metals, combustion reactions, organic compounds, and properties of group 1 and transition metals. It also includes a copy of the periodic table.
This document consists of a chemistry exam paper containing multiple choice and short answer questions testing knowledge of chemical apparatus, reactions, and experimental procedures. The questions cover topics such as identifying experimental set ups, describing chemical reactions and tests, planning investigations, analyzing results, and drawing conclusions from experiments.
This document consists of a 14 page chemistry exam with multiple choice and free response questions covering topics like the halogens, redox reactions, organic chemistry, acid-base reactions, and metals/alloys. It includes diagrams of lab setups and reagents/products. The exam provides space for students to show their work and includes a periodic table reference.
This document consists of three paragraphs summarizing the content of a 16-page biology exam. The exam contains multiple choice and short answer questions about fungi reproduction, acid rain, and sensitivity. It provides context about classifying fungi species, the effects of acid rain, and defining voluntary vs involuntary actions. Tables and figures are referenced to support analyzing trends in sulfur dioxide and sulfur concentrations over time.
This document consists of instructions and questions for a biology exam. It contains 12 pages, with the first 9 pages consisting of exam questions and the last 3 pages being blank. The exam has two sections - Section A contains short answer questions and Section B requires longer answers to two out of three essay questions. The questions cover topics in biology such as human reproduction, cell structure, genetics, the water cycle, osmosis, nutrition, and plant growth.
This document is a 19-page exam for the International General Certificate of Secondary Education (IGCSE) Biology exam. It contains 10 multiple choice and short answer questions covering topics like the respiratory system, photosynthesis, nutrient cycling, food webs, cell structure, genetics, and inherited conditions. Students are instructed to answer all questions directly on the exam paper and work is to be completed in 1 hour and 15 minutes.
1. This document consists of 17 printed pages and 3 blank pages for the Cambridge International Level 1/2 Certificate in Physics.
2. The document is approved for use in England, Wales and Northern Ireland and contains a multiple choice exam from October/November 2014 with 40 questions on topics related to physics.
3. Students are instructed to choose the correct answer for each question and record their choice on an answer sheet within 45 minutes, with each correct answer scoring one mark.
This document consists of a 16 page multiple choice exam for physics. It contains 40 multiple choice questions testing various concepts in physics such as motion, forces, energy, electricity, waves, and nuclear physics. The questions are accompanied by diagrams, graphs, and short paragraphs of information as context for the questions.
This document is a multiple choice exam for physics that contains 40 questions. It covers topics like mechanics, energy, waves, electricity, atomic physics, and more. The questions require analyzing diagrams, graphs, and scenarios to choose the best answer from four options (A, B, C, or D).
This document consists of a 20-page exam for the International General Certificate of Secondary Education in Physics. The exam contains 40 multiple choice questions testing various concepts in physics, including kinematics, forces, energy, waves, electricity, and radioactivity. The questions are presented over two columns on each page with answer choices A, B, C, or D provided.
This document is a 20 page exam for the International General Certificate of Secondary Education Physics exam. It contains 40 multiple choice questions testing various concepts in physics. The questions cover topics such as measurement, motion, forces, energy, electricity, waves, and radioactivity. Students have 45 minutes to complete the exam.
1. This document consists of 18 printed pages and 2 blank pages for a Cambridge International Level 1/Level 2 Certificate in Physics.
2. The document contains a multiple choice exam with 40 questions on topics related to physics. For each question there are four possible answers (A, B, C, D) and students must choose the one they consider correct.
3. The exam covers various concepts in physics including measurement, motion, energy, electricity, magnetism, waves, and radioactivity. Diagrams and tables are provided with some questions.
Taurus Zodiac Sign: Unveiling the Traits, Dates, and Horoscope Insights of th...my Pandit
Dive into the steadfast world of the Taurus Zodiac Sign. Discover the grounded, stable, and logical nature of Taurus individuals, and explore their key personality traits, important dates, and horoscope insights. Learn how the determination and patience of the Taurus sign make them the rock-steady achievers and anchors of the zodiac.
Best practices for project execution and deliveryCLIVE MINCHIN
A select set of project management best practices to keep your project on-track, on-cost and aligned to scope. Many firms have don't have the necessary skills, diligence, methods and oversight of their projects; this leads to slippage, higher costs and longer timeframes. Often firms have a history of projects that simply failed to move the needle. These best practices will help your firm avoid these pitfalls but they require fortitude to apply.
An introduction to the cryptocurrency investment platform Binance Savings.Any kyc Account
Learn how to use Binance Savings to expand your bitcoin holdings. Discover how to maximize your earnings on one of the most reliable cryptocurrency exchange platforms, as well as how to earn interest on your cryptocurrency holdings and the various savings choices available.
Industrial Tech SW: Category Renewal and CreationChristian Dahlen
Every industrial revolution has created a new set of categories and a new set of players.
Multiple new technologies have emerged, but Samsara and C3.ai are only two companies which have gone public so far.
Manufacturing startups constitute the largest pipeline share of unicorns and IPO candidates in the SF Bay Area, and software startups dominate in Germany.
Event Report - SAP Sapphire 2024 Orlando - lots of innovation and old challengesHolger Mueller
Holger Mueller of Constellation Research shares his key takeaways from SAP's Sapphire confernece, held in Orlando, June 3rd till 5th 2024, in the Orange Convention Center.
Understanding User Needs and Satisfying ThemAggregage
https://www.productmanagementtoday.com/frs/26903918/understanding-user-needs-and-satisfying-them
We know we want to create products which our customers find to be valuable. Whether we label it as customer-centric or product-led depends on how long we've been doing product management. There are three challenges we face when doing this. The obvious challenge is figuring out what our users need; the non-obvious challenges are in creating a shared understanding of those needs and in sensing if what we're doing is meeting those needs.
In this webinar, we won't focus on the research methods for discovering user-needs. We will focus on synthesis of the needs we discover, communication and alignment tools, and how we operationalize addressing those needs.
Industry expert Scott Sehlhorst will:
• Introduce a taxonomy for user goals with real world examples
• Present the Onion Diagram, a tool for contextualizing task-level goals
• Illustrate how customer journey maps capture activity-level and task-level goals
• Demonstrate the best approach to selection and prioritization of user-goals to address
• Highlight the crucial benchmarks, observable changes, in ensuring fulfillment of customer needs
3 Simple Steps To Buy Verified Payoneer Account In 2024SEOSMMEARTH
Buy Verified Payoneer Account: Quick and Secure Way to Receive Payments
Buy Verified Payoneer Account With 100% secure documents, [ USA, UK, CA ]. Are you looking for a reliable and safe way to receive payments online? Then you need buy verified Payoneer account ! Payoneer is a global payment platform that allows businesses and individuals to send and receive money in over 200 countries.
If You Want To More Information just Contact Now:
Skype: SEOSMMEARTH
Telegram: @seosmmearth
Gmail: seosmmearth@gmail.com
Anny Serafina Love - Letter of Recommendation by Kellen Harkins, MS.AnnySerafinaLove
This letter, written by Kellen Harkins, Course Director at Full Sail University, commends Anny Love's exemplary performance in the Video Sharing Platforms class. It highlights her dedication, willingness to challenge herself, and exceptional skills in production, editing, and marketing across various video platforms like YouTube, TikTok, and Instagram.
Digital Transformation and IT Strategy Toolkit and TemplatesAurelien Domont, MBA
This Digital Transformation and IT Strategy Toolkit was created by ex-McKinsey, Deloitte and BCG Management Consultants, after more than 5,000 hours of work. It is considered the world's best & most comprehensive Digital Transformation and IT Strategy Toolkit. It includes all the Frameworks, Best Practices & Templates required to successfully undertake the Digital Transformation of your organization and define a robust IT Strategy.
Editable Toolkit to help you reuse our content: 700 Powerpoint slides | 35 Excel sheets | 84 minutes of Video training
This PowerPoint presentation is only a small preview of our Toolkits. For more details, visit www.domontconsulting.com
B2B payments are rapidly changing. Find out the 5 key questions you need to be asking yourself to be sure you are mastering B2B payments today. Learn more at www.BlueSnap.com.
Navigating the world of forex trading can be challenging, especially for beginners. To help you make an informed decision, we have comprehensively compared the best forex brokers in India for 2024. This article, reviewed by Top Forex Brokers Review, will cover featured award winners, the best forex brokers, featured offers, the best copy trading platforms, the best forex brokers for beginners, the best MetaTrader brokers, and recently updated reviews. We will focus on FP Markets, Black Bull, EightCap, IC Markets, and Octa.
The 10 Most Influential Leaders Guiding Corporate Evolution, 2024.pdfthesiliconleaders
In the recent edition, The 10 Most Influential Leaders Guiding Corporate Evolution, 2024, The Silicon Leaders magazine gladly features Dejan Štancer, President of the Global Chamber of Business Leaders (GCBL), along with other leaders.
At Techbox Square, in Singapore, we're not just creative web designers and developers, we're the driving force behind your brand identity. Contact us today.
1. w
w
0610 Biology June 2004
e
tr
.X
w
ap
eP
m
CONTENTS
om
.c
s
er
BIOLOGY ............................................................................................................................ 2
Paper 0610/01 Multiple Choice ..................................................................................................................... 2
Paper 0610/02 Paper 2 (Core) ...................................................................................................................... 3
Paper 0610/03 Paper 3 (Extended)............................................................................................................... 6
Paper 0610/04 Coursework........................................................................................................................... 9
Paper 0610/05 Practical Test ...................................................................................................................... 11
Paper 0610/06 Alternative to Practical ........................................................................................................ 13
1
2. 0610 Biology June 2004
BIOLOGY
Paper 0610/01
Multiple Choice
Question
Number
Key
Question
Number
Key
1
2
3
4
5
D
C
C
B
D
21
22
23
24
25
D
C
C
C
B
6
B
26
D
7
8
9
10
B
B
B
D
27
28
29
30
A
A
C
C
11
12
13
14
15
A
D
C
B
D
31
32
33
34
35
B
B
C
A
D
16
17
18
19
20
D
D
C
A
B
36
37
38
39
40
D
D
C
A
A
General comments
This paper provided a good spread of marks with a very small percentage achieving the maximum. Only one
question was not correctly answered by at least half the candidates.
Comments on specific questions
Question 3
This question was presented in a somewhat unfamiliar form and required candidates carefully to interpret the
information provided before selecting their answer. The responses indicated that there is some confusion
between the terms genus and species. A third of candidates felt that modern people are in the same species
but not the same genus as their ancestors. Significantly, those who chose this option were generally not
able performers on the rest of the test.
2
3. 0610 Biology June 2004
Question 7
There was some difficulty here in recognising a leaf as an organ. All options had a degree of support,
particularly from 25% who believed that a leaf is a tissue. This was not, however, a belief held by able
candidates.
Question 8
Over a quarter of the candidates opted for a diagram of a red blood cell in its normal form when asked to
select one that has changed. The indications are that the concept of osmosis and red blood cells was, by
some, not well understood.
Question 11
Candidates were struggling to differentiate between the graphs showing the effects of temperature and pH
on enzymes with half of them not appreciating that the sudden decline in rate at 60 oC indicates destruction
of the enzyme.
Question 12
A basic misunderstanding, both over the function of the phloem as well as over the properties of organic
chemicals, was exposed by this question, namely that 38% of candidates believe that starch is a chemical
that is translocated in the phloem.
Question 15
It was only the very good candidates who knew that fat is the highest energy food. It appears likely that
carbohydrates rather than fats are linked with energy in the minds of most candidates with over 50% being
attracted by a high-carbohydrate option.
Question 22
This question proved to be a snare for the unwary. Those who immediately linked alcohol with liver opted for
the blood vessel leading blood from the liver, when they should have been reasoning that alcohol is first
absorbed by the gut, then taken to the liver in vessel C.
Question 33
As might be expected, there were no problems at all with this question as it proved to be the easiest on the
paper. Nevertheless, 2% did believe that a cow is a producer - of milk, no doubt!
Question 40
Superficially, this question appears straightforward and not particularly testing, with 79% choosing the correct
option (A). However, several able candidates seemed not to carefully assimilate the information in the
question. Some appeared to miss the arrows showing the direction of water flow, but, more worryingly,
others hinted at the belief that pesticides affect the growth of water plants.
Paper 0610/02
Paper 2 (Core)
General comments
There was considerable evidence, much of it noted in comments about individual questions, of candidates
not reading the questions carefully enough. Thus their responses, often biologically correct, failed to answer
the questions set. There was overall evidence that the candidates tackled questions demanding application
skills better than those requiring them to present knowledge and understanding. The candidates on the
whole completed the paper and appeared to have sufficient time to achieve this.
3
4. 0610 Biology June 2004
Comments on specific questions
Question 1
(a)(i)
(ii)
Few candidates were able to identify the labelled phase as the log phase. It was confused with the
lag phase. Many tried to describe what was occurring during this phase rather than naming it.
It would seem that in a very large number of cases candidates did not note that the graph related to
a population of yeast and their responses suggested that various factors that affect humans or
animals in the wild were the causes for the population not growing any further. It was expected
that suggestions would include factors such as a lack of glucose or other nutrient and the build up
of ethanol or other toxic waste.
(b)
Although the majority of candidates did offer either a word or a symbol equation and not mixed
ones, unfortunately their understanding of the process of fermentation by yeast was very weak.
Some equations dealt with aerobic respiration or anaerobic respiration in mammals while others
seemed to be attempts at a representation of photosynthesis.
(c)
There would seem to be considerable misunderstanding about the long term effects of alcohol in
the human body. Erroneously a range of types of cancer was quoted as well as various forms of
damage to the kidneys and the heart. Many responses were very vague and did little more than
repeat the stem of the question.
Question 2
(a)
A significant proportion of the candidates were able to name the two structures but there was some
confusion as to whether A was the cervix or the uterus.
(b)
Understanding of where the three events occur was poor. Fertilisation was often thought to occur
in either an ovary or the uterus while the production of oestrogen was attributed to most parts of the
system shown in the diagram. A greater proportion of candidates were able to identify the ovaries
as the site of gamete production.
(c)
Again this year many candidates confused primary and secondary sexual characteristics. It was
expected that candidates would be familiar with features such as widening of the hips,
development of mammary glands, growth of pubic and axillary hair and the deposition of
subcutaneous fat. A significant number quoted features that occur in males only.
(d)
Although the question referred to changes in the ovaries and uterus a significant number of
candidates discussed events occurring elsewhere, and gained no credit for this. The responses
revealed considerable confusion in relation to what happens and the sequence of the events.
Candidates should refer to the growth and shedding of the uterine lining and not to its wall or to the
uterus as a whole. Both ovule and ovary were apparently substituted for ovum in many
descriptions.
Question 3
(a)
The vast majority of candidates solved the identification with little difficulty although where errors
occurred it seemed to be between the two cereals with awns, A and D.
(b)
A number of candidates seemed to have overlooked the fact that the question requested
differences between insect and wind pollinated flowers and instead offered responses about
leaves, whole plants, seeds and fruits and also methods of seed dispersal. Candidates should
appreciate that when differences are requested then in their responses they should refer to both
types of flower or in the event that they only make a statement about one only they should make it
absolutely clear which type of flower is being dealt with.
(c)(i)
Candidates should have linked the two ions with the formation of chlorophyll and with proteins. Far
too many responses were very vague and mentioned the use of the ions in growth and
photosynthesis.
4
5. 0610 Biology June 2004
(ii)
There was some confusion over the effect of nitrate ions in water sources with many
misconceptions. These ions are thought by some to have a direct toxic affect on both animals and
plants. They are believed to directly cause anaerobic conditions in the water. Only a few
candidates appreciated that the nitrate ions cause algae and other aquatic plant life to grow
prolifically. This can lead submerged plants to die because of lack of light and this with the death
of many algae leads to a massive increase in bacterial activity. It is this that results in anaerobic
conditions and its consequences.
Question 4
(a)
Candidates need to recognise that data of the type presented in the table should be plotted as a
point graph and should not attempt to display it as a bar chart. Many candidates did not label the
vertical axis and a significant number used a non-linear scale. Some candidates simply listed the
values in the table, in the same order as they are printed, as the vertical scale. Many did not seem
to appreciate that having plotted the points they should either join them or draw a line of best fit, a
skill with which many seemed unfamiliar.
(b)(i)
It was expected that candidates would realise that increased humidity would reduce the rate of
water loss but most seemed to think that the reverse occurred.
(ii)
Many candidates recognised that changes in temperature, wind speed or light intensity could affect
the rate of water loss but it was very unusual for any of them to explain why it had an effect.
(c)
Although a significant number identified xylem as the tissue involved, far fewer realised it had an
additional function in providing support. Responses often reflected confusion with the role of the
phloem.
Question 5
Responses varied reflecting varying degrees of confusion and misunderstanding. There was the inevitable
muddling of haploid and diploid, gamete and zygote and the numbers of pairs and single chromosomes.
More thought that the presence of an X chromosome was indicative of a male than the Y chromosome.
Question 6
Candidates seemed to have a better knowledge and understanding of the digestion of protein than that of
either starch or fat. The most frequent error was not identifying the pancreas as a source of starch digesting
enzyme. There was clearly confusion between the food materials and the end products of digestion.
Question 7
(a)(i)
Although there were a variety of correct responses related to different food chains within the food
web a large majority of candidates were able to quote a correct example.
(ii)
It would seem that a large proportion of candidates failed to note the phrased ‘Using examples from
this food web …’ as they regularly gave definitions or descriptions of both primary and secondary
consumers but omitted to quote examples. There were a few who erroneously quoted examples
that were not part of this web.
(b)(i)
This aspect of the understanding of all ecosystems has been examined many times in the past and
still large numbers of candidates do not appreciate that the source of energy for all food webs is the
sun.
(ii)
Many candidates did not seem to realise that by comparing the percentage of total energy
transferred the factor of the animal’s size is basically eliminated. Only a very few recognised a
difference between the insect and a mammal is the need for the latter to maintain a constant body
temperature, normally above that of the environment, and that this leads to a constant loss of heat
energy and its need for replacement. Thus a smaller percentage of input energy is passed on to
the next generation.
(c)
There are two alternative explanations as to the effect of myxomatosis, in the rabbit population, on
the kestrels. Either suggestion was accepted and credit given for taking the explanation step by
step through the potential chain of events. A large proportion of the candidates gave clear logical
responses.
5
6. 0610 Biology June 2004
Question 8
(a)
It was expected that candidates would describe how additional activity during exercise would cause
a greater rate of respiration in the relevant muscles, a greater demand for oxygen and glucose and
consequently a need for the removal of more carbon dioxide and heat from the muscles. This
would explain why the rate of blood flow was increased.
(b)(i)
Many hormones and other chemical agents were offered in response to this question but relatively
few identified adrenalin as the correct response.
(ii)
A very large proportion of the responses suggested factors that would lead to the heart increasing
blood flow rather than the ways in which the heart could achieve this. Only a very small number
offered both correct responses, increased heart rate and increased stroke volume, but both were
offered singly by many candidates, the former being the more common response.
Paper 0610/03
Paper 3 (Extended)
General comments
This was the first time that candidates had the opportunity to answer the paper in its new format. All the
questions were compulsory (instead of previously choosing two from four Section B questions) and the mark
allocation had increased from 70 to 80 marks. Centres were required to choose the most suitable option for
each candidate, with Paper 3 being appropriate for those likely to gain a grade A to C, although the full range
of grades was available. Many Centres opted appropriately, but some chose to enter weaker candidates
who inevitably struggled with questions containing material from the extended curriculum and more
challenging questions from the core of the syllabus. The change in structure appeared to work well, with a
broader range of questions allowing candidates to demonstrate their knowledge and understanding across
the curriculum content. Even weaker candidates were able to make good attempts at answering some of the
questions, notably Questions 1, 2 and 3. Having all the questions structured helped candidates to keep
their answers focused more and parts of questions did not get overlooked, as has happened in the previous
format. Indeed, Examiners marked very few scripts where parts of questions had not been attempted.
A very good standard of answers was seen, but the paper still discriminated well and there was no evidence
of any candidates running out of time. Examiners felt strongly that the new structure was fairer to the
candidates since, previously, success depended to a certain extent on the choice of Section B questions.
Spellings were variable, even when the correct terms were written in the question. For example, in
Question 3 (d), pancreas was often written as pancrease. The question rubrics were usually followed,
although a sizeable number of candidates failed to follow the instructions given in Question 5 (b) – ‘without
further reference to carbon dioxide’ - filling the available spaces in parts (i), (ii) and (iii) with details that were
irrelevant.
Explanatory questions proved to be the most difficult, with candidates failing to be sufficiently precise with
their terminology. For example, comparative terms, qualifying words and linkages were often omitted.
Comments on specific questions
Question 1
The question was accessible to examinees of all abilities.
(a)(b)
These were answered correctly by most candidates.
(c)
The majority were able to construct the food chain correctly. A few tried to include all the
organisms named in the question stem, while some placed the arrows in the wrong direction.
Some began without a named producer (usually plants instead of grass).
6
7. 0610 Biology June 2004
(d)
This was usually answered well. However, some gave an answer that was too general, such as
‘they can get more food’. The benefits of teamwork were often mentioned, but answers usually
failed to state the increased chance of a kill that would result.
(e)
Most candidates successfully extracted information from the question stem that jackals have
alternative food sources. More imaginative answers stated that jackals would kill sheep in
unprotected flocks. Weaker answers suggested that jackals have other food sources, without
naming them.
(f)
A range of acceptable answers was seen here, including trachea, oesophagus, spinal cord, arteries
and veins. Some thought that the aorta or vena cava is present in the neck. The structures
needed to be named, so vague responses such as blood vessel were not accepted. The term
vertebrate was sometime confused with vertebrae.
(g)
Most were aware that plastics tend to be non-biodegradable and gained a mark. Most went on to
define the term, rather than give an explanation for the problem this would cause. The best
answers referred to problems of visual pollution, scavengers choking on the plastic or the air
pollution caused by burning the plastic collars. Some thought that toxic gases would be given off
as the plastic decayed, or that animals would get trapped in the collars. Vague references to
pollution were common.
Question 2
The question was generally understood and answered well, although part (e) proved to be more challenging.
(a)
Most were able to give an accurate definition of the term balanced diet. Some candidates tried to
list all the essential food classes, but usually omitted at least one, although they had been listed in
the stem of part (b). Many failed to use the terms nutrients or foodstuffs in their definition.
(b)
Carbohydrates and fats were usually correctly selected. Occasionally, protein or fibre was chosen
as a second answer.
(c)(i)
While most candidates identified student Z as being obese, too many confused the other two. It
was apparent that they had not used the chart, Fig. 2.1, in their identification.
(ii)
This was generally answered well, with an increased chance of a heart attack and diabetes being
the most common responses. A few described the causes of obesity instead of suggesting the
health problems. There were occasional vague references to heart or breathing problems, without
giving more detail.
(d)
Most could name the units making up all three food molecules. A small minority only gave one
answer for fats, although the value of the question indicated that, in total, four answers would be
needed.
(e)(i)
Most candidates correctly stated enzyme or biological catalyst. A few stated catalyst unqualified,
or named a specific enzyme.
(ii)
This was answered less well. Correct explanations involved the need for the molecules to be small
and soluble to pass through the wall of the intestine or through capillary walls into the blood stream.
Very few were aware of the use of the small molecules in synthesising new compounds. Some
candidates tried to answer the question in terms of increasing surface area, which was not relevant
here. Misconceptions included references to small molecules being easier to swallow or to be
digested.
Question 3
Again, candidates tended to score well on this question. Weak candidates struggled with parts (c) and (d).
(a)
The calculation was well within the abilities of the majority of candidates.
(b)
All parts were well answered. A few lost marks for identifying tissues such as alveoli and sweat
glands instead of organs. A significant number thought that the liver is responsible for forming
urine.
7
8. 0610 Biology June 2004
(c)(i)
(ii)
(d)
A surprising number of answers failed to state the change in volume of sweat and urine before
explaining the change, so the explanation was not accepted without a correct volume statement.
While an explanation for an increase in sweat was usually correct, fewer could relate a decrease in
urine production to the increase in water lost through more sweat being lost, or to a need to
maintain the water content of the blood. Occasional references to the effect of the secretion of
ADH were accepted.
This was usually answered correctly, although many candidates struggled with the spelling.
This was well answered: the better candidates all gained maximum marks. Where confusion did
arise, it was generally between glucose and sucrose, excretion and secretion, glycogen and starch,
or liver and pancreas.
Question 4
Only the best candidates could gain high marks on this question. It separated candidates who understood
the topic from those who had learned statements by rote.
(a)
Surprisingly, while most were aware of the increase in surface area that root hair cells create, few
stated that the cells occur in large numbers, or that they contain large numbers of mitochondria to
provide energy for active uptake of minerals.
(b)(i)
Most candidates could give an accurate definition of active transport. A few got the gradient the
wrong way round.
(ii)
(c)
Candidates generally understand that active uptake requires energy, provided by respiration.
Some candidates need to study this topic in more detail.
(i)
This is in the core of the syllabus, but few answers displayed a sound knowledge of the
modifications of xylem tissue for its function of transporting water and minerals. Where lignin was
mentioned, many thought that it is present to withstand the pressure of water inside the xylem,
rather than preventing the collapse of the vessels as water is drawn through them.
(ii)
Better answers referred to transpiration and some of the mechanisms involved in achieving water
movement. However, vague, irrelevant descriptions involving osmosis were common, with weak
candidates offering only a definition of the process.
Question 5
This proved to be a more challenging question than expected, with few candidates gaining very high marks.
It discriminated well between the more able and less able candidates. There were some very confused
ideas concerning global warming, the ozone layer, CFCs and ultraviolet radiation.
(a)
Although there were some good answers about the greenhouse effect and its possible
consequences, there were also some very confused ones where carbon dioxide was described as
a poisonous gas blamed for depleting the ozone layer and causing acid rain.
(b)
A significant number of candidates ignored the instruction not to make further reference to carbon
dioxide, giving near-repeat answers to those already credited in part (a).
(i)
Answers were equally acceptable if they related to a coal-fired or nuclear power station. Few
candidates referred to the burning of fossil fuels, even though they were aware of the production of
sulphur dioxide and its effects. Vague references to damage to buildings or plants or animals were
common. Often, lists of gases (including carbon dioxide, carbon monoxide, oxides of nitrogen and
sulphur dioxide) were given as waste products from the power station. These were then all linked
with specific effects such as acid rain, making the answer biologically incorrect.
(ii)
In this question, candidates were generally clearer about the effects of deforestation and were
more precise about soil erosion, changes to the water cycle and habitat loss. However, very few
were aware of the dangers to the lungs of particulates from wood smoke. Too often, carbon
monoxide was identified as being produced when wood is burned, which is unlikely, particularly if
the wood is burned outside. Again there was confusion about how the ozone layer can be
damaged.
8
9. 0610 Biology June 2004
(iii)
Lists of gases were also given in this part. Candidates need to be reminded that they will lose
marks if they give lists of items containing some that are wrong. Motor vehicles tend to generate
oxides of nitrogen rather than sulphur dioxide. Obvious details such as the formation of oxides of
nitrogen being the result of the combustion of petrol (or diesel or gasoline) were frequently absent.
Few candidates were aware of the presence of lead in some fuels, or of the harm that lead or
particulates can do to humans when inhaled. Indeed, little knowledge was shown of the
differences in polluting effects of petrol and diesel. Better answers highlighted the dangers of
carbon monoxide to human health.
Question 6
(a)
Candidates using punnett squares to illustrate their genetic crosses tended to make fewer errors
than those drawing traditional genetic crosses. In the traditional format, the cross between the
genotypes of the parents was often omitted and the labelling of parent line, gametes and F1 were
rarely given. Candidates should be encouraged to draw clear lines to show how the F1 genotypes
are derived from the gametes.
Most were able to complete the crosses. Marks were sometimes lost due to carelessness, while
not all candidates stated the ratios produced. In part (ii), the phenotype of the cat associated with
the ratio was not always identified.
(b)
The better candidates were able to apply their knowledge of co-dominance to this unfamiliar
situation and suggested that the cat would have fur of an intermediate length. Many, however,
suggested that the cat would have a mixture of fur length.
Question 7
(a)
Almost all the candidates could state the differences between the composition of colostrum and
normal breast milk.
(b)
The calculation was usually completed correctly, with the working shown. This is important since, if
the candidate makes an error in deriving the answer, a mark may still be awarded for working with
the correct figures. Some candidates showed little understanding of how to work out the answer,
while others used the figures for colostrum in their calculation.
(c)(i)
Orange juice was a universal answer, with few alternatives seen.
(ii)
(d)
A surprising number of answers showed a complete lack of knowledge about the relationship
between sugar and bacteria on the teeth. Many thought that it was the sugar itself that causes
cavities. Very few recognised that sucking the sugary drink through a teat prolonged the contact of
sugar with the teeth.
Good answers were seen here. However, the term symptom was not understood by all, with some
responses describing the effect of an iron deficiency on the blood.
Answer: (b) 20 g.
Paper 0610/04
Coursework
General comments
An increasing number of Centres are entering candidates for this paper. The majority of Centres have
assessed their candidates appropriately, and it is encouraging to find that few adjustments are now needed
to bring the standards from different Centres into line with one another.
In most cases, around 6 to 12 tasks have been used. Some Centres prefer to assess only one or two skills
with each task, whilst others assess three together. It is now rare to see attempts to assess C1 and C4 on
the same task, although unfortunately a few instances of this did occur.
9
10. 0610 Biology June 2004
Most Centres use criterion-based, descriptive mark schemes, at least for skills C2, C3 and C4. Many,
however, are using well-constructed tick list schemes for C1, and a few also use these for the other three
skills. Tick lists are easy to apply, but great care is needed when constructing them. A few Centres are still
attempting to arrive at a mark simply by adding up ticks, which is not acceptable as it does not relate the
candidate’s mark to the descriptors for each level of performance.
Paperwork is generally accurately completed. One or two Centres, however, appear to have taken
insufficient care in ensuring that marks are correctly transcribed from the candidates’ work to the various
forms, and that addition is correct. It is important to build in some type of checking procedure, as it is easy to
make mistakes and these are often detrimental to the candidates.
Comments on specific skills
Skill C1
Almost any practical task can be used for assessing Skill C1. Some Centres have chosen to use tick lists,
while others use descriptive schemes. Not all Centres included evidence for their assessments of this Skill
with their sample. It is very important to do this.
Skill C2
This Skill involves observation and recording. Many Centres have chosen to use some tasks involving
drawing, and others involving taking numerical readings – for example of temperature, time or volume – and
recording these in a results chart.
Skill C3
Assessment of this Skill can only be done effectively where an experiment produces numerical results.
Many Centres assess it using the same tasks as C2. This Skill involves processing results, drawing
conclusions and evaluating results. Processing is normally assessed by calculations and/or graph-drawing,
and most candidates show good graphing skills. In some Centres, computer-drawn graphs are used. This is
acceptable, so long as the candidate is in control of the graph’s format, including choice of graph type, axes
and of scales, and the way that the line is drawn. Evaluation is a high-level skill, and is a good discriminator
between weaker and stronger candidates.
It is now rare to see Centres using paper-and-pencil exercises to try to assess this Skill. This is
unacceptable; like all of these Skills, C3 must be assessed using results obtained either by the candidates
themselves, or from a demonstration involving them.
Skill C4
This Skill, involving planning and carrying out an investigation, is more time-consuming than the others, and
most Centres offer their candidates only two attempts, usually assessed towards the end of the course.
Some use the same exercise for assessment of Skills C2 and C3. While this is certainly possible, it needs
considerable experience and care if it is to work successfully. The tasks used here vary widely. They
normally grow out of related work that the candidates have done, so that they have had experience of a
suitable technique that they can adapt to a new situation.
Care needs to be taken that the plan, the actual method used and the evaluation are a candidate’s own,
individual work. In some cases, it appeared that candidates had worked together, which is unacceptable. If
necessary, the writing of the plan should be done under controlled conditions in the classroom or laboratory,
so that the teacher can guarantee that each candidate’s plan is constructed with no outside help.
10
11. 0610 Biology June 2004
Paper 0610/05
Practical Test
General comments
It was pleasing to note that few candidates performed poorly on this paper and an encouraging number
performed really well, demonstrating an ability to follow instructions, draw diagrams, analyse and make
reasoned suggestions.
It was appreciated that some Centres experienced some difficulty with the materials in Question 1 and in
obtaining suitable specimens for Question 2. This was taken into account when the mark scheme was
finalised. Every effort was made to credit candidates who had followed instructions and to use their
observations and results to reward deductions made. The fact that most Centres supplied information
concerning the problems and specimens was useful to the Examiners, as was the inclusion of pictures that
were, in some cases, used. Centres are reminded that this aspect of the examination (adequate completion
of the Supervisor’s Report) is very important. Centres are also reminded that they can contact CIE with any
queries that they may have. It is particularly important the Centres contact CIE if they are unable to supply a
specimen or piece of apparatus as alternative solutions can be suggested to ensure that their candidates are
not at a disadvantage. Centres are also advised to ensure that reagents work well, giving a clear result, and
they should, preferably, be freshly prepared and tested before the examination.
Comments on specific questions
Question 1
(a)
Most candidates gained both marks here. The most frequent error was to record ‘no change’ for
adding water to iodine. This is ambiguous and so was not credited.
(b)(i)
In order to gain these marks, 16 distinct drops should have been drawn and the two groups of 8
clearly separated, either with a ‘gap’ or labelled. Some candidates had misunderstood and put a
large drop consisting of 8 drops in one corner of a tile and another large drop of 8 drops in the
opposite corner. Pitted or smooth tiles could have been used, so the number of depressions
available should not have posed a problem as long as enough space was available. Candidates
are advised to read ahead a little in order to be clear about what is required.
(ii)
Candidates who scored well in this question are those who followed good basic procedures in
preparing a table. All lines should be neatly ruled. The table should be capable of being used to
record the information required in a clear manner. Rows and/or columns should have suitable
headings, including correct units if appropriate (the recognised abbreviation for minutes is ‘min.’
and not ‘m.’ which is used for ‘metres’). Enough space should be available to record all the results
that are required. Candidates are also expected to use lines to include the headings in the table.
An example of a suitable table (but not the only correct answer) is shown below:
Time (mins)
Colour when added to iodine solution
A
B
1
2
3
4
5
6
7
8
(iii)
The question asked candidates to record observations. Conclusions such as ‘starch present’ were
not appropriate. Candidates should be encouraged to record what they see and not to enter
comments such as ‘nothing’ or ‘no result’.
11
12. 0610 Biology June 2004
(c)
Candidates were marked on the basis of their individual results. There was no indication from the
paper that sodium chloride would speed up the reaction, although many candidates assumed that
this would be the case, even when their results did not support this fact. Clearly many candidates
struggled to interpret their results and Examiners were sympathetic in looking for reasonable
deductions to credit. Many results indicated that the sodium chloride produced no effect on the
activity of the enzyme but candidates were reluctant to state this, even if their results clearly
showed it. A typical example is that of the candidate who has results of ‘yellow’ for both A and B
for all times. These results clearly show that the enzyme alone and the enzyme with sodium
chloride both broke down the starch within 1 minute. There is no difference in the behaviour of A
and B. However, the candidate confidently states that ‘sodium chloride speeds up the reaction’.
There is no evidence to support this and so this deduction cannot be made. Some confusion was
seen concerning the role of the amylase, starch and iodine even though this information was given
in the stem at the beginning of the question and in (a). Even candidates who had obtained and
recorded correct colour changes for the presence and absence of starch in (a) would state that the
enzyme had broken down the starch because a blue/black colour was present.
(d)
It was disappointing to see how many candidates experienced difficulty with a basic scientific
principle. While some commented on the need to dilute the amylase, few went on to explain that
this was to make the concentrations or volumes equal. Some candidates appeared to think that it
would alter the pH. Weaker candidates failed to gain any marks, not even one for indicating a fair
test or control, while even good candidates did not express themselves clearly enough to gain both
marks.
(e)
This part of the question proved to be challenging for many candidates. Some simply had little idea
of how to describe a controlled experiment and only made suggestions of how to alter pH or test for
starch. There were some excellent descriptions that were clear to follow and would work well but
many were confused and it was difficult to see precisely what the candidate was attempting to
suggest. Confusion concerning the role of amylase, saliva, starch and iodine was evident. It was
not unusual for candidates to forget to add either starch or amylase when they had described in
detail how to get solutions of different pH. Many were unsure which chemicals would produce
acidic or alkaline conditions. The candidates were not required to suggest possible results, but
many did - and spent much of their answer doing so. Time and effort was wasted in this way.
Question 2
(a)(i)
(ii)
(b)
(i)
Clear, large diagrams were drawn by a large number of candidates. Some sketching of the outline
was seen. Candidates should be encouraged to use a single line. While most diagrams were of a
reasonable size, some were too small to see details clearly. Candidates should be advised to
make drawings at least 5 cm. in length. Some detail of texture is also normally required, in this
case some idea of venation on the wing. Although being asked to label two parts of the fruit, many
candidates did not and therefore lost marks. Centres who provided, as asked, a labelled diagram
of the fruit provided to their candidates, gave valuable assistance to the Examiners.
Candidates had been asked to draw a line to indicate where they were taking their measurements
and this was not done in a significant proportion of cases. In these cases, it might not be clear
where the measurement had come from. A significant number of candidates measured length very
inaccurately, even when they had followed the instructions concerning drawing the line. Examiners
do check the measurements and will not award the mark if outside a reasonable tolerance. Some
candidates did not include units and therefore lost a mark. Magnification is a common calculation
that would be expected on this paper, but many candidates seemed to have little idea of how to
perform the calculation. No units should be given for magnification and it is considered that
answers to more than 1 decimal place give a degree of accuracy that is not practical. Candidates
should be advised to give results to the nearest whole number or to 1 decimal place.
The question clearly instructs candidates to cut around the outline of the Acer fruit on page 6. It
was surprising how many candidates did not do this and, as a result, were unable to draw
accurately around it on the grid provided.
Although this is not demanding mathematically, it proved to be a challenge to many candidates.
They were expected to use the squares on the grid to provide an estimate of surface area. There
are very many candidates who have little concept of size and units of measurement and
consequently they do not realise that the answers that they give are improbable. One ‘large’
square had an area of 1 cm2 but the ‘small’ square had an area of 4 mm2 and not 1 mm2. This was
a common error. Although a range of answers was accepted, some answers were so approximate
as to be meaningless.
12
13. 0610 Biology June 2004
(ii)
(c)
Some excellent explanations were seen but many were poorly expressed. Many candidates simply
stated that they had multiplied length by width, which was credited with one mark. It was pleasing
to see a significant number of candidates who appreciated that the fruit had two surfaces.
The key words in this question were ‘describe’ and ‘environmental’. Answers such as ‘wind affects
the distance travelled’ did not contain enough detail to be awarded a mark. Candidates were
expected to make statements such as ‘on a windy day the fruit will travel further’. This actually
described the effect that the wind would have. Some candidates simply described modifications of
the plant while others wrote about pollination, which was not relevant.
Paper 0610/06
Alternative to Practical
General comments
The paper included a range of differentiated questions for candidates to answer to show their experimental
skills and ability C1 to C4, as outlined in the syllabus booklet page 17-19.
In most Examiners’ allocations there were Centres with good candidates of high ability and all Examiners
reported that candidates appeared to have adequate time to complete the paper. Many candidates
managed to achieve high scores and all of the points on the paper were achieved by different candidates.
The standard of English seen on the scripts was high and the drawing and line graph were generally
constructed using a pencil.
Range of marks noted 0 to 40.
Comments on specific questions
Question 1
This question was based on the passage of water molecules into or out of onion epidermal cells when placed
in sugar solutions of different concentrations.
(a)
The width measurement of four different cells was required. The line to be measured was clearly
printed on the drawings. Most candidates correctly recorded the same measurement for Fig. 1.1
and used SI units either cm or mm. Unfortunately, there were a significant number of candidates
who failed to record which unit of measurement was used. The line in Fig. 1.3 was shorter, as the
cell was plasmolysed and in Fig. 1.4 the line was longer as this cell was turgid and the cell contents
had increased.
(b)
The identification of the solution, in which each of the cells had been placed, was considered
separately to the explanation.
Candidates who had carried out this type of practical were able to identify the solution and offer an
explanation involving osmosis and the diffusion of water either into the cell (Fig. 1.4) or out of the
cell (Fig. 1.3). In the case of the cell in Fig. 1.2 this diffusion was balanced and so there was no net
movement of water. Some candidates answered with reference to the ‘passage of water molecules
from a region of their higher concentration to a region of their lower concentration’, as given in the
core syllabus, or some referred to the concept of water potential gradient as in the supplement.
The direction of movement needed to be clearly expressed either into or out of the cell as relevant.
Although there were many excellent answers, some candidates need to be clear about these
concepts and to identify the direction of movement of the water molecules and not the sugar
molecules. Candidates are often confused over terms such as osmotic potentials, concentration of
solutions and solvents.
13
14. 0610 Biology June 2004
Question 2
The question was based on a series of recorded results for an enzyme, amylase on the breakdown of starch
using iodine solution to test for any starch which may still be present in the reaction mixtures.
(a)(i)
Table 2.1 recorded the colour changes of a sample of the reaction mixture in three test tubes A, B
and C. The third sentence in the introduction clearly stated that the starch had been completely
digested when the orange brown iodine solution does not change colour.
Most candidates recorded the times for tubes A and C correctly but others recorded the change
from black to dark brown where the starch was only partially broken down.
(ii)
Tube C had 1 cm³ of 0.5% sodium chloride added instead of water. This made the breakdown of
the starch faster by at least 7 minutes. An explanation for this was not required as it is beyond the
syllabus. Enzymes are defined as proteins that function as biological catalysts. Sodium chloride is
an inorganic compound it speeds up the reaction it does not affect pH as some candidates
described.
(iii)
The role for tube B in this investigation was to act as a control for tube A so the colour changes
might be compared. Most candidates realised this point but there were some candidates who
thought that tube B ‘controlled the reaction’ and did not appreciate the comparison aspect. Other
candidates described the effect of denaturing the enzyme by boiling but did not continue to
describe the role of this to the overall investigation.
(b)
This section was based on planning a different investigation, namely, to show the effect of pH on
the activity of amylase. (Skill C4). If candidates had carried out this investigation or practised
planning an investigation then by including experimental details the full marks were gained readily.
The plan should involve controlling the concentrations and volumes of reactants (starch and
amylase), the conditions such as the temperature and using similar apparatus and testing methods,
so there is only one variable, that of pH. Many of the details were given in the introduction to the
first experiment.
The method for controlling pH by the use of buffers or addition of diluted acids or alkaline
substances was credited as also the idea of repeating the experiment to verify the results. Some
candidates expressed confused ideas concerning pH and thought sodium chloride (see (a)(ii))
controlled pH.
Many of the candidates did follow the details given and their plans could be easily followed.
However, other candidates gave a description of digestion of starch (as well as other foods) in the
alimentary canal and failed to refer to any experimental details. A few candidates misread the
instructions and incorrectly described details of an experiment to follow changes in pH as the
breakdown of starch took place.
Question 3
The third question was the longest and was based on the structure of wind dispersed fruits and the handling
of a set of data, and short questions concerning the dispersal of these fruits.
(a)(i)
The candidates were required to make a large drawing of one of the two joined fruits shown in
Fig. 3.1. Candidates could choose which fruit to draw. Although many candidates did follow this
rubric and drew a single fruit, there were a significant number of candidates who drew both fruits
joined together. A few candidates drew fruits which were completely different resembling lemons
or tomatoes.
The standard of drawing varied from the accurate, large, well-proportioned version using a
sharpened pencil for the outline to the small, rough and sketchy outlined one showing poor
proportions which was difficult to recognise as one of the fruits.
The label to mark the position of the seed should be in the upper portion of the fruit above the
lighter line with the wing-like extension below. The seed is not located at the junction line between
the fruits and not along the wing-like extension. The position of the seed was the only label
requested.
14
15. 0610 Biology June 2004
(ii)
Most candidates correctly measured the length of the fruit in Fig. 3.1 and on their drawing and
calculated the magnification. For those candidates who had drawn two fruits and therefore
measured both fruits the calculation was credited. Magnification does not have a unit. This was a
common error.
A few candidates expressed the magnification as a ratio.
(iii)
Two methods of calculating surface area were recognised. Some candidates meticulously counted
squares and included half squares covered by the fruits (sometimes it was the whole area minus
the squares surrounding the fruit). Others measured the length and width of the fruit and
calculated the surface area mathematically.
The method chosen was clear from the
measurements on the Fig. 3.1.
The units, mm² or cm², were often confused or not given.
Consideration was given to those candidates who based the drawing, magnification and
determination of surface area on two fruits instead of a single fruit.
(b)(i)
This part involved the calculation of five mean distances to complete the final column in Table 3.1.
Most candidates carried out the calculations correctly. Unfortunately, some candidates only
recorded totals, failing to divide these totals by the number of results, five. There was plenty of
spare space at the end of the question for rough calculations but some candidates used the
Examiner’s margin.
(ii)
Most candidates attempted to plot an accurate line graph with the values for the surface area of the
model fruit in cm³ on the x-axis and the distance travelled/cm on the y- axis. Some candidates
used a ruled line point to point and others a line of best fit. Either of these methods was acceptable
providing that the line was accurately drawn. The scale caused problems for candidates. The
range of values for the surface area of fruit increased by 32 cm² for each set of repeated values of
distance travelled and an even scale was required. If this range started from 30 cm² (instead of
0 cm²) and used one mm square to represent 2 cm² an even scale filled the printed grid. The
vertical scale for the mean distance travelled in cms for a value of 0 or 25 to 50 cm an even scale
could be used to fill the printed grid.
Common errors noted included the incorrect orientation of axes; incomplete labelling of the axes or
not labelling the axes; use of scales which were not even; incorrect plotting; extrapolation of the
line for the graph beyond the plotted points. A few candidates inappropriately plotted a histogram
when the question requested a line graph.
(iii)
Many candidates described the relationship between the surface area and the mean distance
travelled by the fruit as almost linear where the increase in surface area of the wing-like extension
of the fruit carried the fruit further from the parent plant. The data showed an almost a linear
relationship and gave the opportunity for candidates to express this by referring to the gradient of
the line plotted on the graph.
(iv)
The importance of seed dispersal away from the parent plant was discussed by most candidates
with reference to reducing over-crowding of the seeds on germination thereby reducing also the
competition between seedlings for space, water or light. Some candidates inappropriately
discussed pollination, increasing variability, natural selection or avoiding disease.
15