This document is a 16-page Life Sciences question paper for Grade 12 from the February/March 2013 National Senior Certificate exams in South Africa. It consists of 4 sections with multiple choice, short answer, and longer answer questions testing knowledge of topics like genetics, evolution, and human origins. The instructions state that students have 2.5 hours to complete the paper and must answer all questions, showing their work in the provided answer book.
This document provides instructions for a Life Sciences exam consisting of 15 pages with 150 marks over 2.5 hours. It instructs students to answer all questions, write answers in the answer book, number answers correctly, and do all drawings in pencil with labels in ink. Diagrams are not necessarily to scale. Students must use a non-programmable calculator, protractor, and compass where needed. The exam consists of two sections. Section A contains multiple choice, matching, and short answer questions. Section B involves labeling diagrams and short answer questions related to DNA, RNA, protein synthesis, and meiosis.
This 10-page memorandum provides marking guidelines for a Life Sciences P1 exam consisting of 150 marks and taken by full-time candidates in February/March 2013. It outlines 20 principles related to marking, including how to mark answers that provide more or less information than required or have incorrect sequencing. The memorandum also provides answer keys and mark allocations for 4 sections worth a total of 150 marks. Section A covers multiple choice, terminology, and genetics inheritance questions. Section B addresses DNA structure, sex-linked inheritance, protein synthesis, and meiosis. Section C involves human evolution topics and a graphing activity. Section D covers genetics principles like phenotypes and genotypes.
This document provides instructions for students taking the Grade 12 Life Sciences exam. It consists of three sections with a total of 150 marks over 21⁄2 hours. Students must answer all questions, writing their answers in the answer book and numbering them correctly. Diagrams should be drawn in pencil and labeled in ink. Calculators, protractors, and compasses may be used.
This document provides instructions for a Life Sciences exam consisting of 3 sections worth 150 marks over 21⁄2 hours. Section A is worth 50 marks and contains multiple choice, matching, and short answer questions testing various concepts in Life Sciences. Section B is worth 30 marks and contains diagram labeling, sequencing, and longer answer questions on topics like meiosis and protein synthesis. Section C is worth 9 marks and contains labeling and short answer questions testing knowledge of the female reproductive system. The exam paper consists of 14 pages and students are instructed to answer all questions, show their work, and draw diagrams as required. Calculators and drawing tools are permitted.
This document provides the memorandum for marking Life Sciences Paper 1 from November 2010 for the National Senior Certificate in South Africa. It outlines 20 principles for marking, including how to allocate marks for partial or incorrect answers. The memorandum then provides the answers and marking schemes for questions in Sections A, B and C of the paper. It gives the correct responses and number of marks awarded for each answer line or part. In total 150 marks were available for the paper.
This document contains instructions for a 150 mark, 2.5 hour Life Sciences exam for Grade 12. It outlines:
- The number of questions and pages in the paper
- Instructions that students must answer all questions, write answers in the answer book, and number them correctly
- Information on drawings, diagrams, and materials allowed
- The exam contains 3 sections: Section A with 7 multiple choice and descriptive questions worth 50 marks, Section B with 4 extended response questions worth 30 marks, and Section C with 1 extended response question worth 30 marks.
This memorandum provides answers and guidance for grading a Life Sciences exam consisting of 12 pages. It includes answers to multiple choice questions, short answer questions, and longer essay questions on topics relating to human reproduction, genetics, and biotechnology. Scoring rubrics are provided for questions involving diagrams, graphs, and experimental designs. The memorandum also notes common student errors to avoid for certain questions.
This document is a 10 page memorandum for a Life Sciences exam consisting of 4 sections and 15 questions. It provides the answers and explanations for each question, along with the number of marks allocated to each part. The memorandum also includes rubrics for marking diagrams and explanations. In total, there are 150 marks available for the exam.
This document provides instructions for a Life Sciences exam consisting of 15 pages with 150 marks over 2.5 hours. It instructs students to answer all questions, write answers in the answer book, number answers correctly, and do all drawings in pencil with labels in ink. Diagrams are not necessarily to scale. Students must use a non-programmable calculator, protractor, and compass where needed. The exam consists of two sections. Section A contains multiple choice, matching, and short answer questions. Section B involves labeling diagrams and short answer questions related to DNA, RNA, protein synthesis, and meiosis.
This 10-page memorandum provides marking guidelines for a Life Sciences P1 exam consisting of 150 marks and taken by full-time candidates in February/March 2013. It outlines 20 principles related to marking, including how to mark answers that provide more or less information than required or have incorrect sequencing. The memorandum also provides answer keys and mark allocations for 4 sections worth a total of 150 marks. Section A covers multiple choice, terminology, and genetics inheritance questions. Section B addresses DNA structure, sex-linked inheritance, protein synthesis, and meiosis. Section C involves human evolution topics and a graphing activity. Section D covers genetics principles like phenotypes and genotypes.
This document provides instructions for students taking the Grade 12 Life Sciences exam. It consists of three sections with a total of 150 marks over 21⁄2 hours. Students must answer all questions, writing their answers in the answer book and numbering them correctly. Diagrams should be drawn in pencil and labeled in ink. Calculators, protractors, and compasses may be used.
This document provides instructions for a Life Sciences exam consisting of 3 sections worth 150 marks over 21⁄2 hours. Section A is worth 50 marks and contains multiple choice, matching, and short answer questions testing various concepts in Life Sciences. Section B is worth 30 marks and contains diagram labeling, sequencing, and longer answer questions on topics like meiosis and protein synthesis. Section C is worth 9 marks and contains labeling and short answer questions testing knowledge of the female reproductive system. The exam paper consists of 14 pages and students are instructed to answer all questions, show their work, and draw diagrams as required. Calculators and drawing tools are permitted.
This document provides the memorandum for marking Life Sciences Paper 1 from November 2010 for the National Senior Certificate in South Africa. It outlines 20 principles for marking, including how to allocate marks for partial or incorrect answers. The memorandum then provides the answers and marking schemes for questions in Sections A, B and C of the paper. It gives the correct responses and number of marks awarded for each answer line or part. In total 150 marks were available for the paper.
This document contains instructions for a 150 mark, 2.5 hour Life Sciences exam for Grade 12. It outlines:
- The number of questions and pages in the paper
- Instructions that students must answer all questions, write answers in the answer book, and number them correctly
- Information on drawings, diagrams, and materials allowed
- The exam contains 3 sections: Section A with 7 multiple choice and descriptive questions worth 50 marks, Section B with 4 extended response questions worth 30 marks, and Section C with 1 extended response question worth 30 marks.
This memorandum provides answers and guidance for grading a Life Sciences exam consisting of 12 pages. It includes answers to multiple choice questions, short answer questions, and longer essay questions on topics relating to human reproduction, genetics, and biotechnology. Scoring rubrics are provided for questions involving diagrams, graphs, and experimental designs. The memorandum also notes common student errors to avoid for certain questions.
This document is a 10 page memorandum for a Life Sciences exam consisting of 4 sections and 15 questions. It provides the answers and explanations for each question, along with the number of marks allocated to each part. The memorandum also includes rubrics for marking diagrams and explanations. In total, there are 150 marks available for the exam.
This document provides marking guidelines for grading Life Sciences papers in South Africa. It details 20 principles for markers to follow, such as marking the first three reasons given if more than three are provided. It also notes that abbreviations must be defined and that changes to memoranda require moderator approval. The document is signed, showing moderator consensus on the policies.
Higher History exam (paper 2) - 2011 (marking instructions)mrmarr
This document provides the 2011 marking instructions for the Scottish Higher History exam. It gives guidance to examiners on how to mark different types of questions involving the evaluation of sources and the use of recall. For source evaluation questions, up to 2 marks can be given for evaluating the source's provenance and content, and up to 2 marks for relevant recalled information. For contextualization questions involving one source, up to 4 marks can be given for interpreting the source and up to 7 marks for using relevant recall. Examiners are told to annotate scripts to indicate when credit is being given for provenance, source material, comparisons, and recalled information. Sample questions are provided as examples of how the marking instructions should be applied.
This document contains a specimen exam for the Modern Studies course in Scotland. It is divided into three sections covering Democracy in Scotland/UK, Social Issues in the UK, and International Issues. Each section contains multiple choice questions assessing understanding of topics covered. Sources provided relate to the House of Lords, legal highs, and viewpoints on banning legal highs. The exam tests knowledge and ability to analyze sources to answer questions.
National 5 History exam - 2015 (marking instructions)mrmarr
The document provides general marking principles and detailed marking instructions for the 2015 National 5 History exam in Scotland. It outlines the marking codes that will be used and provides examples of how to apply the codes for different types of questions. The marking instructions provide guidance on how many marks can be awarded for certain types of responses, such as descriptions, explanations, comparisons, and evaluations. They also give subject-specific examples for how to interpret candidate answers for each question type.
This document contains 5 math quiz questions with their corresponding answers. The first question asks to identify the wrong step in a proof that attempts to show 2 = 1 by dividing by zero. The next two questions ask to identify the biggest number with 4 ones and the smallest two-digit integer. The last two questions ask to count the triangles and rectangles in given figures. The answers provided identify the division by zero error and give the numerical answers to the remaining questions.
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This 12-page document appears to be an exam for the Cambridge International General Certificate of Secondary Education in Chemistry. It consists of questions testing knowledge of key chemistry concepts related to kinetics, thermodynamics, organic chemistry, metals, and other topics. The questions include multiple choice, short answer, and longer explanations requiring diagrams or equations. The document provides instructions for candidates on how to answer the questions and includes a periodic table of elements as a reference.
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Guida per il technical writer che usa Argo e per il traduttore che traduce sui file MS Excel o XML esportati da Argo
A Complete Guide to the IELTS Writing Test - GTIELTSBackup
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The document discusses different reading tasks in the PTE Academic exam. It focuses on describing the Reading and Writing Blanks task, which involves filling blanks in a passage with the correct words. It provides 8 grammar rules to help with this task, such as using nouns after articles and adjectives between articles and nouns. It emphasizes completing this task within 2 minutes per passage, using context clues and grammar rules to eliminate options and fill blanks confidently. The document also briefly outlines the MCQ Multiple Answers task and recommends spending no more than 1 minute on each passage by focusing on keywords to locate correct answers.
The document provides information about a practice exam for the Scottish National Qualifications in History in 2017. It lists 11 possible exam sections on various topics in history, and provides the page number where the questions for each section can be found. The sections include topics like Northern Britain from the Iron Age to 1034, Scotland's independence and kingship from 1249-1334, Renaissance Italy, Scotland from the Treaty of Union to the Enlightenment, and several others.
The document provides guidance for students on evaluating the effectiveness of their personal development plan in volleyball. It discusses evaluating different elements using the SOFITT acronym and focusing on frequency. Students are instructed to write a paragraph evaluating if the frequency they applied to their training was effective or not. The paragraph should include an identification of the element, a judgement providing details, and a value statement explaining the impact. Examples are provided to demonstrate the expected structure and content.
The document is a mark scheme that provides guidance for examiners on how to award marks for answers on the International General Certificate of Secondary Education (IGCSE) Physics exam. It outlines the marking criteria and rules that examiners should follow to maintain consistency in scoring responses. Key points include how method marks, independent marks, and numerical/compensatory marks are assigned. The mark scheme also provides examples of answers for several physics questions and shows the marks allocated to different elements within sample student responses.
This memorandum provides marking guidelines for Life Sciences Paper 2 for the February/March 2013 examination in South Africa. It consists of 9 pages outlining the principles for marking, answers to questions in Sections A, B and C, and allocation of marks. The memorandum addresses topics related to human reproduction, genetics, ecosystems, population ecology, and endocrine system regulation.
This memorandum provides marking guidelines for Life Sciences Paper 2. It consists of 20 pages detailing the answers and marks allocated for each question. Principles for marking include stopping when maximum marks are reached, marking the first answer if more than required are given, and crediting relevant parts of longer answers. Abbreviations must be defined to receive marks. Diagrams or flow charts lose marks if descriptions are required.
This document provides marking guidelines for grading Life Sciences papers in South Africa. It details 20 principles for markers to follow, such as marking the first three reasons given if more than three are provided. It also notes that abbreviations must be defined and that changes to memoranda require moderator approval. The document is signed, showing moderator consensus on the policies.
Higher History exam (paper 2) - 2011 (marking instructions)mrmarr
This document provides the 2011 marking instructions for the Scottish Higher History exam. It gives guidance to examiners on how to mark different types of questions involving the evaluation of sources and the use of recall. For source evaluation questions, up to 2 marks can be given for evaluating the source's provenance and content, and up to 2 marks for relevant recalled information. For contextualization questions involving one source, up to 4 marks can be given for interpreting the source and up to 7 marks for using relevant recall. Examiners are told to annotate scripts to indicate when credit is being given for provenance, source material, comparisons, and recalled information. Sample questions are provided as examples of how the marking instructions should be applied.
This document contains a specimen exam for the Modern Studies course in Scotland. It is divided into three sections covering Democracy in Scotland/UK, Social Issues in the UK, and International Issues. Each section contains multiple choice questions assessing understanding of topics covered. Sources provided relate to the House of Lords, legal highs, and viewpoints on banning legal highs. The exam tests knowledge and ability to analyze sources to answer questions.
National 5 History exam - 2015 (marking instructions)mrmarr
The document provides general marking principles and detailed marking instructions for the 2015 National 5 History exam in Scotland. It outlines the marking codes that will be used and provides examples of how to apply the codes for different types of questions. The marking instructions provide guidance on how many marks can be awarded for certain types of responses, such as descriptions, explanations, comparisons, and evaluations. They also give subject-specific examples for how to interpret candidate answers for each question type.
This document contains 5 math quiz questions with their corresponding answers. The first question asks to identify the wrong step in a proof that attempts to show 2 = 1 by dividing by zero. The next two questions ask to identify the biggest number with 4 ones and the smallest two-digit integer. The last two questions ask to count the triangles and rectangles in given figures. The answers provided identify the division by zero error and give the numerical answers to the remaining questions.
For helpful CXC Maths Multiple Choice Videos please click below
These videos are very helpful
https://oke.io/dUqlSrd
https://oke.io/UWfOCCP
https://oke.io/FrCDQ
This 12-page document appears to be an exam for the Cambridge International General Certificate of Secondary Education in Chemistry. It consists of questions testing knowledge of key chemistry concepts related to kinetics, thermodynamics, organic chemistry, metals, and other topics. The questions include multiple choice, short answer, and longer explanations requiring diagrams or equations. The document provides instructions for candidates on how to answer the questions and includes a periodic table of elements as a reference.
Argo CCMS: come tradurre testi esportando e importando file MS Excel e XMLKEA s.r.l.
Argo CCMS: come tradurre testi usando le funzioni Esporta / Importa Office (formati supportati: MS Excel e XML)
Guida per il technical writer che usa Argo e per il traduttore che traduce sui file MS Excel o XML esportati da Argo
A Complete Guide to the IELTS Writing Test - GTIELTSBackup
Facebook: https://www.facebook.com/ieltsbackup
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Send us your feedback & suggestions: info@ieltsbackup.com
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The document discusses different reading tasks in the PTE Academic exam. It focuses on describing the Reading and Writing Blanks task, which involves filling blanks in a passage with the correct words. It provides 8 grammar rules to help with this task, such as using nouns after articles and adjectives between articles and nouns. It emphasizes completing this task within 2 minutes per passage, using context clues and grammar rules to eliminate options and fill blanks confidently. The document also briefly outlines the MCQ Multiple Answers task and recommends spending no more than 1 minute on each passage by focusing on keywords to locate correct answers.
The document provides information about a practice exam for the Scottish National Qualifications in History in 2017. It lists 11 possible exam sections on various topics in history, and provides the page number where the questions for each section can be found. The sections include topics like Northern Britain from the Iron Age to 1034, Scotland's independence and kingship from 1249-1334, Renaissance Italy, Scotland from the Treaty of Union to the Enlightenment, and several others.
The document provides guidance for students on evaluating the effectiveness of their personal development plan in volleyball. It discusses evaluating different elements using the SOFITT acronym and focusing on frequency. Students are instructed to write a paragraph evaluating if the frequency they applied to their training was effective or not. The paragraph should include an identification of the element, a judgement providing details, and a value statement explaining the impact. Examples are provided to demonstrate the expected structure and content.
The document is a mark scheme that provides guidance for examiners on how to award marks for answers on the International General Certificate of Secondary Education (IGCSE) Physics exam. It outlines the marking criteria and rules that examiners should follow to maintain consistency in scoring responses. Key points include how method marks, independent marks, and numerical/compensatory marks are assigned. The mark scheme also provides examples of answers for several physics questions and shows the marks allocated to different elements within sample student responses.
This memorandum provides marking guidelines for Life Sciences Paper 2 for the February/March 2013 examination in South Africa. It consists of 9 pages outlining the principles for marking, answers to questions in Sections A, B and C, and allocation of marks. The memorandum addresses topics related to human reproduction, genetics, ecosystems, population ecology, and endocrine system regulation.
This memorandum provides marking guidelines for Life Sciences Paper 2. It consists of 20 pages detailing the answers and marks allocated for each question. Principles for marking include stopping when maximum marks are reached, marking the first answer if more than required are given, and crediting relevant parts of longer answers. Abbreviations must be defined to receive marks. Diagrams or flow charts lose marks if descriptions are required.
This document provides principles for marking the Life Sciences memorandum for the 2011 National Senior Certificate Grade 12 examination. It outlines 20 principles related to marking, including how to mark answers that provide extra information, partial processes, diagrams instead of descriptions, non-recognized abbreviations, and spelling errors. It also provides guidance on marking different language responses and adhering only to approved marking memoranda.
This document provides examination guidelines for the Grade 12 Life Sciences exam in South Africa. It consists of 19 pages covering: the format and weighting of the exam papers; the formal assessment program and sequence of topics; and an elaboration of the content to be assessed for each topic, including DNA, meiosis, reproduction, genetics and inheritance. The topics will be assessed across two question papers that contain short answers, structured questions and an essay. The guidelines are intended to clarify the scope of the exam and assist teachers in preparing learners.
This document contains assessment exemplars for Life Sciences for Grade 10, including control tests, a research project, and practical tasks. It provides teacher guidelines, assessment rubrics, and worksheets for learners for each assessment. The introductions explain that the exemplars are meant to be used for continuous assessment throughout the year. They assess the three learning outcomes, with the tests and project assessing mastery of content and skills, and the practical tasks assessing skills. Guidelines are provided for implementing the research project and practical activities, including classroom management, technology use, and thinking strategies.
This memorandum consists of 11 pages and provides grading guidelines for answering questions about Life Sciences. It includes 20 principles for marking answers, such as crediting parts of responses even if the whole process isn't described. The memorandum also provides the answers to sample questions on topics like human reproduction, genetics, ecology and the human nervous and endocrine systems.
This memorandum provides guidelines for marking the 2011 Life Sciences Paper 2 for the National Senior Certificate in South Africa. It consists of 20 principles to ensure consistent and fair marking. Some key principles include: awarding marks for the first few reasons/examples provided, even if incorrect; accepting answers that demonstrate understanding despite differences in format; and not penalizing for spelling errors if the word is recognizable. The memorandum also provides mark allocations for each question and sub-question.
The memorandum provides principles for marking Life Sciences papers in 2012. It details 20 marking principles, including crediting relevant parts of answers even if extra information is provided, marking the first few reasons or examples given, and being sensitive to answers stated differently but conveying the same meaning. The memorandum also addresses aspects like spelling, abbreviations, diagrams, flow charts, and language.
This document provides instructions for a Life Sciences exam. It consists of 15 pages and students have 2.5 hours to complete it. The instructions state that students must answer all questions, write answers in the answer book provided, number answers according to the question paper, present drawings according to instructions, and write neatly. It also provides information about the number of marks allocated, use of calculators and drawing tools, and copyright notice.
This document contains instructions for a Grade 12 Life Sciences exam. It consists of 17 pages and students have 2.5 hours to complete it. The exam contains multiple choice questions, terminology questions, matching questions and short answer questions testing knowledge of human anatomy and physiology, genetics, ecology and other topics. Students must answer all questions in the answer book provided and show all working where required. Diagrams should be drawn in pencil. Calculators and other aids are permitted.
- Charles Darwin developed the theory of evolution by natural selection to explain how life evolves over time through descent with modification from common ancestors.
- During his voyage on the HMS Beagle, Darwin made extensive observations of wildlife and fossils. He noticed patterns of biodiversity including variations between species in different locations.
- Darwin was influenced by ideas from scientists like Lyell, Hutton, and Lamarck. Lyell and Hutton proposed that geological changes occurred gradually over long periods, influencing Darwin's view of biological changes also requiring vast timescales.
This document is the cover page for a Life Sciences exam consisting of 16 pages. It provides instructions for candidates taking the exam, including answering all questions, writing answers in the answer book, numbering answers correctly, presenting answers as instructed, using pencil for drawings, only drawing diagrams when asked, and writing neatly. It also allows for the use of a calculator, protractor, and compass where necessary.
This document provides instructions for a Grade 12 Life Sciences exam. It consists of 14 pages and students have 2.5 hours to complete it. The exam contains 3 sections. Section A has 10 multiple choice questions worth 1 or 2 marks each, and short answer questions worth 1-8 marks. Section B contains diagram and graph interpretation questions worth 1-14 marks. Section C involves investigating the resistance of mosquitoes to DDT over time, with associated graphing and analysis questions worth 1-6 marks. Students are instructed to show all working, use scientific terms correctly, and answer all questions in full sentences in the answer book provided.
This document is a 14-page question paper for the Life Sciences P1 exam with the following details:
- Marks: 150
- Time: 2.5 hours
- Consists of 7 sections with multiple choice, matching, short answer and long answer questions testing knowledge of topics like meiosis, genetics, the menstrual cycle, protein synthesis and DNA profiling. Instructions are provided on how to answer the questions and various diagrams accompany some questions.
This document provides instructions for a Life Sciences exam consisting of 13 pages and 150 marks over 2.5 hours. It is divided into 3 sections. Section A contains multiple choice and matching questions about topics in evolution, genetics, human origins, and inheritance patterns. Section B asks students to represent genetic crosses, discuss advantages and disadvantages of genetic engineering, and interpret data on human height. Section C contains diagrams of skulls and asks students to identify species, compare evolutionary trends, and describe evidence for the African origin of humans.
This document provides instructions for a Life Sciences exam consisting of 17 pages. It outlines that students must answer all questions, writing answers in the answer book and numbering them correctly. Diagrams should be drawn in pencil with labels in ink. Calculators and other equipment may be used. Students should write neatly and legibly. The exam is worth 150 marks and must be completed in 2.5 hours.
This document provides instructions for a Life Sciences exam consisting of 150 marks over 2.5 hours. It is divided into three sections: Section A with 50 marks, Section B with 60 marks, and Section C with 40 marks. The paper contains various types of questions including multiple choice, matching columns, labeling diagrams, short answers and longer explanations. Students are instructed to answer all questions in their answer book and show all working where necessary. They are permitted to use a calculator, protractor and compass during the exam.
This document is a 16-page Life Sciences question paper for Grade 12 students taking a test. It consists of various multiple choice and short answer questions testing knowledge of topics like sexual reproduction, population ecology, human physiology, and more. The questions are formatted in numbered sections and subsections, with space provided to write answers directly in the test booklet.
This document provides instructions for a Life Sciences exam that will take place over 150 minutes. It consists of 15 pages and covers topics related to human anatomy and genetics. The exam is divided into 3 sections. Section A contains multiple choice and short answer questions. Section B focuses on human reproduction and inheritance. Section C addresses genetics concepts like inheritance patterns, genetic crosses and co-dominance. Students are instructed to answer all questions, show their work, and label diagrams clearly. Calculators and drawing tools are permitted.
This document provides instructions for a Life Sciences exam consisting of three sections worth a total of 150 marks over 21⁄2 hours. Section A is worth 50 marks and includes multiple choice, matching, and short answer questions testing concepts in evolution, ecology and microbiology. Section B is worth 30 marks for each of two structured questions on topics like pollution indicators, deforestation, and comparative anatomy. Section C consists of an essay worth 40 marks. Students are instructed to answer all questions, show workings, use diagrams where required, and write neatly.
1. The document is a sample biology exam paper for Class XII consisting of 5 sections with a total of 26 questions. It provides instructions for the exam, including question types and number of marks for each.
2. The sections cover very short answer (1 mark), short answer I (2 marks), short answer II (3 marks), value based question (4 marks), and long answer questions (5 marks). Sample questions are provided covering topics in biology.
3. Detailed instructions are given about the number and type of questions, internal choices available, and general guidelines for answering the paper.
This document provides information about an additional practice test for Class XII Biology in 2023-24. It contains 33 questions across 5 sections (A-E). Section A has 16 one-mark questions. Section B has 5 two-mark questions. Section C has 7 three-mark questions. Section D has 2 four-mark case-based questions. Section E has 3 five-mark questions. The test covers a range of topics in biology including genetics, evolution, ecology, and human physiology. Students must attempt all questions, which may include multiple choice, short answer, or case-based questions.
Heredity is the fascinating study of how traits are passed down from one generation to the next. It forms the foundation for understanding the similarities and differences among living organisms, providing insights into the mechanisms of inheritance. From the color of our eyes to the texture of our hair, heredity influences a wide array of physical and physiological characteristics in all living beings.
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Cbse class 10 science chapter 9 heredity and evolution2015 11-09Sameer Bhatta
This document contains a practice test for CBSE Class 10 Science Chapter 9 on Heredity and Evolution. It includes 25 multiple choice questions and true/false questions to test understanding of concepts related to inheritance of traits, genetic variation, natural selection, evolution, and Mendel's experiments with garden peas. The questions cover topics such as dominant and recessive traits, genetic drift, inheritance of sex chromosomes, DNA as the source of genetic information, and more.
The document is a model paper for the Biology exam (12th standard) for the Jammu and Kashmir State Board of School Education. It contains questions testing knowledge of topics in Zoology and Botany. The Zoology section contains short answer and objective type questions about reproduction, Darwin's theory of natural selection, genetics, and diseases. The Botany section similarly contains short answer and objective type questions testing knowledge of topics such as dominance, ecosystems, pollution, and plant propagation.
This document provides the instructions and content for a sample biology exam consisting of 26 questions across 5 sections (A-E). Section A contains 5 short answer questions worth 1 mark each. Section B contains 5 short answer questions worth 2 marks each. Section C contains 11 short answer questions worth 3 marks each. Section D contains 1 value-based question worth 4 marks. Section E contains 3 long answer questions worth 5 marks each, with internal choices provided. The document provides examples of question content assessing topics such as tissue culture, cellular defense mechanisms, assisted reproduction techniques, PCR, genetics, evolution, disease, biotechnology, and ecosystems.
This document provides the instructions and content for a sample biology exam consisting of 26 questions across 5 sections (A-E). Section A contains 5 short answer questions worth 1 mark each. Section B contains 5 short answer questions worth 2 marks each. Section C contains 11 short answer questions worth 3 marks each. Section D contains 1 value-based question worth 4 marks. Section E contains 3 long answer questions worth 5 marks each, with internal choices provided. The document provides examples of question content assessing topics such as tissue culture, cellular defense mechanisms, assisted reproduction techniques, PCR, genetics, evolution, disease, biotechnology, and ecosystems.
In-class introduction to basic Punnett square set-up and problem s.docxbradburgess22840
In-class introduction to basic Punnett square set-up and problem solving, Part 1
Problem-solving tips:
· A Punnett square allows you to predict the possible genetic outcome of children based on the genetic make-up of the parents.
· First, read the problem and figure out whether the trait of interest or genetic disorder is found on the dominant allele or the recessive allele because that will have an impact on how you interpret the results of the Punnett square.
· Select a letter to represent the trait or disorder and define the dominant and recessive alleles. For example: For eye color, B (dominant) = brown eyes and b (recessive) = blue eyes. For achondroplasia (dwarfism), A (dominant) = achondroplasia and a (recessive) = normal allele.
· If it is a sex-linked question, remember to include the sexual genotypes of the parents (XX for mom and XY for dad).
· Write down all possible genotypes & phenotypes and use this information to help you set up the Punnett square.
1. Practice question on a human trait. In reality, eye color is controlled by multiple genes and is a complex trait. For simplicity, we’ll assume that brown eyes are dominant to blue eyes. Answer the questions below.
a) Select a letter for this trait and define the dominant and recessive alleles.
B (dominant) =
b (recessive) =
b) Write down all possible genotypes and phenotypes for individuals in the population
Possible genotypes
(the 2 alleles an individual has)
Possible phenotypes (the physical appearance of a trait)
Homozygous dominant individuals
Homozygous recessive individuals
Heterozygous individuals
c) Set up the Punnett square and solve this problem. Kristy is heterozygous and Mark has blue eyes. What percentage of their offspring will have blue eyes?
Kristy's genotype
Mark's genotype
a) Select a letter for this genetic condition and define the dominant and recessive alleles.
F (dominant) =
f (recessive) =
b) Write down all possible genotypes and phenotypes for individuals in the population
Possible genotypes
(the 2 alleles an individual has)
Possible phenotypes (the physical appearance of a trait)
Homozygous dominant individuals
Homozygous recessive individuals
Heterozygous individuals
c) Set up the Punnett square and solve this problem. Kristy and Mark are carriers for cystic fibrosis. The term carrier is only used when a condition is on the recessive allele. Carriers are heterozygous individuals who are normal and show no symptoms of the disorder, but they have the ability to pass on the mutated recessive allele to their offspring. What percentage of their children will be normal? What percentage of their children will be carriers?
Kristy's genotype
Mark's genotype
2. Practice question on a genetic condition. Cystic fibrosis (CF) is an autosomal, recessive condition that results in mucus buildup in the lungs and digestive system organs. As a result, CF .
This document contains instructions for homework assignment #2 in a genetics course. It includes questions about gene expression, mutation, protein function, recombination, and cancer genetics. Students are asked to answer questions about promoter sequences, start/stop codons, amino acid changes, Holliday junction formation, cancer hotspots, and pedigrees. Diagrams illustrate chromosome structure, gene fusions, and potential recombination outcomes.
Similar to Life sciences p1 feb march 2013 version 1 eng (20)
The document summarizes human reproduction. It describes sexual reproduction involving the fusion of egg and sperm cells. The male reproductive system produces sperm in the testes and transfers them through the penis during intercourse. The female reproductive system involves ovaries releasing eggs, fallopian tubes and uterus where fertilization and fetal development occur. The menstrual cycle and process of fertilization are also outlined.
1. The document defines evolution as gradual changes in organisms over generations due to natural selection. It discusses key figures in the development of evolutionary theory like Lamarck, Darwin, and Wallace.
2. Mechanisms of evolution include genetic variation, inheritance of traits, natural selection of advantageous variations, and accumulation of small changes over long periods of time leading to new species.
3. Evidence for evolution comes from fossils that show gradual changes in ancient species over millions of years, as well as anatomical, genetic, and biochemical similarities between living and extinct species, indicating common ancestry.
1) Fossil evidence from sites in South Africa like Sterkfontein provide insight into early hominids that lived over 3 million years ago, including Australopithecus africanus.
2) As hominids evolved, they exhibited skeletal changes associated with bipedalism as well as increases in brain size and cultural adaptations like tool use.
3) Genetic and fossil evidence supports the 'Out of Africa' theory where modern humans evolved in Africa around 200,000 years ago and migrated elsewhere, replacing earlier hominid species like Neanderthals.
Meiosis is a cell division process that produces gametes, or sex cells, with half the normal number of chromosomes. It occurs in two stages: Meiosis I splits homologous chromosome pairs, resulting in haploid cells, and Meiosis II splits the remaining sister chromatids into individual chromosomes, resulting in four haploid cells. This ensures that offspring receive a mixture of maternal and paternal chromosomes and introduces genetic variation through processes like crossing over during prophase I. Meiosis is essential for sexual reproduction, as it maintains the chromosome number between generations and produces genetic diversity in offspring.
This document discusses genetics and inheritance of genetic diseases. It covers Gregor Mendel's experiments with pea plants which laid the foundations of genetics, including genes, alleles, dominant and recessive traits. It also discusses chromosomes, genetic crosses, sex-linked inheritance and examples of genetic disorders like cystic fibrosis and muscular dystrophy. The role of mutations in causing genetic diseases as well as the process of genetic counseling is summarized.
DNA controls cellular activities and protein synthesis. It is found in the cell nucleus as a double-stranded helix made up of nucleotides. DNA replicates itself using DNA polymerase and stores the genetic code in genes that determine protein sequences. During transcription, a complementary mRNA strand is produced from DNA in the nucleus. Translation then occurs on ribosomes in the cytoplasm, where tRNA brings amino acids to the ribosome according to mRNA codons, assembling proteins from the genetic code carried by DNA.
This document discusses speciation and the factors that can lead to the formation of new species. It outlines two main types of speciation: allopatric speciation which is caused by geographic isolation, and sympatric speciation which does not require a large geographic barrier. Factors that can influence speciation include genetic variation due to isolation, inbreeding within small isolated populations, outbreeding between unrelated individuals, founder effects in small groups colonizing new areas, population bottlenecks from catastrophic events, and reproductive isolation through mechanisms like breeding at different times or adapting to different pollinators.
(1) This document provides instructions for a Life Sciences exam consisting of 3 sections with multiple choice, matching, and short answer questions. It gives the time allotted, 150 marks, and details that all answers must be written in the answer book and drawings done in pencil.
(2) Section A includes 7 multiple choice questions testing content knowledge, 7 short answer questions requiring biological terms, and 6 matching questions. Section B has short answer questions on evolution, adaptations, natural selection, and speciation. Section C addresses disease transmission, resource use, and human evolution.
The document is an 11-page memorandum for a Life Sciences exam consisting of principles for marking, answers to exam questions, and a section on marking criteria. It provides concise summaries and the essential information needed to mark exam responses in 3 sentences or less.
This 10-page memorandum provides marking guidelines for a Life Sciences P2 examination consisting of 150 marks. It details 20 marking principles, including how to mark answers that provide more information than required or have sequencing and language issues. The memorandum then provides answer keys for 50 marks of section A multiple choice and structured questions, 60 marks of section B short answer and diagram labeling questions, and 40 marks of section C essay questions on topics like population growth and endocrine system function.
This document is a 16-page exam paper for Life Sciences P2 from February/March 2010. It contains instructions for the exam, which is divided into two sections worth a total of 150 marks and takes 2.5 hours. Section A contains multiple choice and short answer questions testing concepts related to evolution, ecology, genetics and the timeline of life on Earth. Section B includes several longer answer questions requiring explanations and descriptions related to topics like natural selection, Lamarckism, water pollution and plant uses.
This memorandum consists of 11 pages and provides answers and marking schemes for questions in Life Sciences P2 from February/March 2010. Section A contains multiple choice and short answer questions on topics such as evolution, classification of organisms, geological time periods, and human evolution. Section B involves longer answer questions on natural selection, inheritance of acquired characteristics, environmental issues, and river pollution. Section C contains questions on plant germination, data analysis, human evolution, and fisheries management. The memorandum provides detailed answers and point allocations for each question.
1. Copyright reserved Please turn over
MARKS: 150
TIME: 2½ hours
This question paper consists of 16 pages.
LIFE SCIENCES P1
VERSION 1 (NEW CONTENT) FOR FULL-TIME CANDIDATES
FEBRUARY/MARCH 2013
NATIONAL
SENIOR CERTIFICATE
GRADE 12
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INSTRUCTIONS AND INFORMATION
Read the following instructions carefully before answering the questions.
1.
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Answer ALL the questions.
Write ALL the answers in your ANSWER BOOK.
Start the answers to each question at the top of a NEW page.
Number the answers correctly according to the numbering system used in this question paper.
Present your answers according to the instructions of each question.
ALL drawings should be done in pencil and labelled in blue or black ink.
Draw diagrams or flow charts only when asked to do so.
The diagrams in this question paper are NOT necessarily drawn to scale.
Do NOT use graph paper.
You must use a non-programmable calculator, protractor and a compass, where necessary.
Write neatly and legibly.
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SECTION A
QUESTION 1
1.1
Various options are provided as possible answers to the following questions. Choose the correct answer and write only the letter (A to D) next to the question number (1.1.1 to 1.1.10) in the ANSWER BOOK, for example 1.1.11 D.
1.1.1
Which ONE of the following is the best definition of a species?
A
B
C
D
A population of similar animals which can interbreed
A population of organisms which breed to produce fertile offspring
A community of organisms which can interbreed
A population of organisms with similar characteristics
1.1.2
What causes the genetic disorder where some males have the sex chromosomes XXY?
A
B
C
D
A sex-linked recessive allele
Non-disjunction of chromosomes during meiosis
Two sperm cells fertilise one ovum
Crossing-over during meiosis
1.1.3
The chromosome complement of a human individual who inherits an X chromosome from the father, is ...
A
B
C
D
44 and XX.
44 and XY.
46 and XX.
46 and XY.
1.1.4
Which ONE of the following is an example of artificial selection?
A
B
C
D
DDT resistance in mosquitoes
The development of different species of tortoise from a common ancestor
The decreasing effect of antibiotics on bacteria
Breeding dairy cattle to increase milk production
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1.1.5
Studies have shown that the number of dark moths in a woodland area next to an industrial area is related to the air pollution levels in the atmosphere. When the levels of pollution increase, trees become black from the smoke. Moths are eaten by birds in this area.
Which ONE of the following best describes what would happen to the number of dark moths when air pollution levels change?
AIR POLLUTION LEVELS
NUMBER OF DARK MOTHS
A
Increase
Remain the same
B
Decrease
Increase
C
Increase
Decrease
D
Decrease
Decrease
1.1.6
What percentage of adenine bases is present in a DNA molecule with 2 000 bases, if 400 of the bases are cytosine?
A
B
C
D
20%
30%
40%
60%
1.1.7
The diagram below shows changes in cell mass and DNA mass during two cell cycles.
It can be concluded from the graph that during the cell cycle ...
A
B
C
D
the interphase is the longest phase.
the cell is dividing between 24 and 36 hours.
replication takes place between 0 and 12 hours.
cytokinesis takes place at 12 and 36 hours.
Increase in DNA mass per nucleus (arbitrary units)
Time (hours)
Increase in cell mass (arbitrary units)
2
1
0
0 12 24 36 48
2
1
0
DNA mass
cell mass
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1.1.8
Two parents both have blood group A. Their child has blood group O. What is the best explanation for this pattern of inheritance?
A
B
C
D
The child has inherited the blood group directly from a grandparent.
The parents are homozygous for the blood group alleles.
The parents are heterozygous for the blood group alleles.
There has been a mutation in the blood group alleles.
1.1.9
The result of profiling various DNA samples in a criminal investigation is shown below.
Which conclusion about the crime could the DNA analyst draw?
A
B
C
D
Only suspect X was involved.
Only suspect Y was involved.
Suspects X and Y were both involved.
Neither suspect X nor Y was involved.
1.1.10
The table below shows some genotypes and phenotypes associated with a form of anaemia.
GENOTYPE
PHENOTYPE
HbA HbA
Unaffected
HbA HbS
Partial sickle-cell anaemia
HbS HbS
Severe sickle-cell anaemia
A person who has partial sickle-cell anaemia and an unaffected person have a child together. What are the chances of the child having severe sickle-cell anaemia?
A
B
C
D
100%
50%
25%
0% (10 x 2)
(20)
1 2 3 4 5
Key:
1 Blood sample of victim
2 Blood sample of suspect X
3 Blood sample of suspect Y
4 First sample of DNA from the crime scene
5 Second sample of DNA from the crime scene
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1.2
Give the correct biological term for each of the following descriptions. Write only the term next to the question number (1.2.1 to 1.2.7) in the ANSWER BOOK.
1.2.1
1.2.2
1.2.3
1.2.4
1.2.5
1.2.6
1.2.7
The linking of the present-day distribution of organisms with the past movements of continental plates
The elimination of a species from the Earth
A point where the exchange of genetic material occurs during crossing-over
The stage in the process of the formation of a protein determined by the codons in the mRNA
The type of inheritance which has a range of intermediate phenotypes for a particular trait
An inherited disorder in which blood fails to clot properly
The position of a gene in a chromosome
(7)
1.3
Indicate whether each of the statements in COLUMN I applies to A ONLY, B ONLY, BOTH A AND B or NONE of the items in COLUMN II. Write A only, B only, both A and B, or none next to the question number (1.3.1 to 1.3.8) in the ANSWER BOOK.
COLUMN I
COLUMN II
1.3.1
Discovered the double helical structure of DNA
A: Francis Crick
B: James Watson
1.3.2
A process which can detect mutant genes in an individual
A: Genetic counselling
B: Genetic testing
1.3.3
The breeding of organisms over many generations in order to achieve a desirable phenotype
A: Cloning
B: Artificial selection
1.3.4
Introduces variation within a species
A: Random mating
B: Mutation
1.3.5
An advantage of polyploidy in agriculture
A: Increase in the size of fruit
B: Increase in the size of flowers
1.3.6
The type of cell division that takes place in angiosperm plants
A: Mitosis
B: Meiosis
1.3.7
Influences the inheritance of blood groups
A: Codominance
B: Multiple alleles
1.3.8
Bonds that holds amino acids together in a protein molecule
A: Hydrogen bonds
B: Peptide bonds
(8 x 2)
(16)
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1.4
The pedigree diagram below traces the inheritance of vestigial (reduced in size) and normal wing characteristics in fruit flies. Study the diagram and answer the questions that follow.
1.4.1
1.4.2
State the dominant wing characteristic of the flies used in these crosses.
Use the letters G and g and write down the genotype of the following:
(1)
(a)
(b)
A
J
(1)
(1)
1.4.3
If fruit fly C was crossed with a male having vestigial wings, what would be the possible genotype(s) of the offspring?
(4)
(7)
TOTAL SECTION A:
50
G
H
I
J
B
E
D
F
A
C
Vestigial female fruit fly
Normal male
fruit fly
Vestigial male
fruit fly
Normal female
fruit fly
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SECTION B
QUESTION 2
2.1
The diagram below shows part of a DNA molecule in a nucleus just before cell division.
2.1.1
Identify the parts labelled:
(a)
(b)
3
4
(1)
(1)
2.1.2
Identify the nitrogenous bases labelled:
(a)
(b)
1
2
(1)
(1)
2.1.3
Explain why the diagram above represents replication and not transcription.
(2)
(6)
T
1
2
3
4
A
G
C
T
C
C
T
G
A
T
KEY:
- adenine
- guanine
- thymine
- cytosine
A
G
T
C
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2.2
A rare form of rickets in humans is caused by a sex-linked dominant allele (R) which is carried on the X-chromosome. An affected female, whose father was unaffected, married an unaffected male.
2.2.1
2.2.2
2.2.3
2.2.4
Determine the possible genotypes and phenotypes of their offspring by representing a genetic cross.
What is the percentage chance that they will have a child who is an unaffected male?
Explain why this disorder, although it is sex-linked, does NOT affect males only.
This genetic disorder is caused by a gene mutation in which the DNA triplet CAG is altered to TAG.
(6)
(2)
(2)
(a)
(b)
Name this type of mutation.
Describe how the type of mutation mentioned in QUESTION 2.2.4(a) will affect the structure of the protein it codes for.
(1)
(2)
2.2.5
Give TWO reasons why this couple should undergo genetic counselling before having children.
(2)
(15)
2.3
Ribonuclease is an enzyme made up of 127 amino acids.
2.3.1
2.3.2
What is the minimum number of DNA bases needed to code for amino acids of this enzyme?
The sequence of DNA bases coding for seven amino acids in the enzyme ribonuclease is:
GTT TAC TAC TCT TCT TCT TTA
The number of each type of amino acid coded for by this sequence of DNA bases is shown in the table below.
AMINO ACID
NUMBER OF AMINO ACIDS PRESENT
Arg
3
Met
2
Gly
1
Asn
1
The first amino acid in this enzyme is Gly which is coded for by GTT in DNA. Use the DNA base sequence and the table above to work out the sequence of the remaining amino acids in this part of the enzyme.
(1)
(3)
(4)
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2.4
Study the diagrams below representing various phases of meiosis in an organism.
DIAGRAM A
DIAGRAM B
DIAGRAM C
2.4.1
2.4.2
2.4.3
2.4.4
Which diagram (A, B or C) represents meiosis I?
Suggest why the chromosomes in diagram B will be genetically different from that of the parent cell at the beginning of meiosis.
How many chromosomes will each daughter cell have at the end of this cell division?
Give TWO reasons why this type of cell division is important.
(1)
(1)
(1)
(2)
(5)
[30]
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QUESTION 3
3.1
Professor Lee Berger and his colleagues studied the fossils they found in a cave at the Cradle of Humankind. The skeletons from the cave are ranked amongst the most complete finds to date. The adult female, Australopithecus sediba, was remarkably well preserved and some of the following characteristics were identified:
Some characteristics of Australopithecus sediba:
• A small brain size
• Bipedal
• Smaller canines
• Projecting nose
• Small body size
[Adapted from 'Part Ape Part Human', Josh Fischmann, National Geographic, August 2011]
3.1.1
3.1.2
3.1.3
Write down THREE characteristics from the list above that also apply to the Homo species.
State TWO advantages of A. sediba being bipedal.
Professor Berger called Australopithecus sediba a transitional fossil. Using the information in the list above, explain why he called A. sediba a species in transition.
(3)
(2)
(2)
(7)
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3.2
Study the table below, which indicates some of the hominid fossils found in the world and answer the questions that follow.
SPECIES
REGION WHERE IT WAS FOUND
PERIOD OF EXISTENCE (WHEN IT LIVED)
Australopithecus afarensis
Eastern Africa
3,4–2,8 mya
Australopithecus africanus
Southern Africa
2,1–2,8 mya
Australopithecus sediba
Southern Africa
2,0–1,9 mya
Homo habilis
Sub-Saharan (Africa)
2,3–1,4 mya
Homo erectus
Africa, Europe, Asia
1,5–0,2 mya
Homo heidelbergensis
Europe, China
0,6–0,35 mya
Homo neanderthalensis
Europe, Western Asia
0,35–0,03 mya
Homo sapiens
Worldwide
0,2 mya–present
[Adapted from 'The Evolutionary Road', Jamie Shreeve, National Geographic, July 2010]
3.2.1
3.2.2
3.2.3
Explain why the information in the table supports the 'Out of Africa' hypothesis.
If a fossil of Australopithecus afarensis, dated 3,2 mya, is found in Asia, explain the implications for the 'Out of Africa' hypothesis.
Describe TWO genetic lines of evidence that support the 'Out of Africa' hypothesis.
(3)
(2)
(4)
(9)
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3.3
Study the analogous and homologous structures below, which can be used as evidence for evolution and answer the questions that follow.
3.3.1
Identify TWO structures in the diagram that are:
(a)
(b)
Analogous
Homologous
(2)
(2)
3.3.2
Describe how the homologous structures named in QUESTION 3.3.1(b) give evidence for evolution.
(2)
(6)
Forelimb of a human
Insect wing
Forelimb of a bat
Examples of homologous and analogous structures
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3.4
The diagram below shows five closely related species of finches found on the mainland and on four nearby islands.
Describe how the different species on the four islands evolved over many generations from the original ancestor on the mainland.
(8)
[30]
TOTAL SECTION B:
60
Closely related species of finches found on the mainland and on four nearby islands
Island 3
Island 1
Island 2
Island 4
Mainland
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SECTION C
QUESTION 4
4.1
A group of learners investigated the frequency of dominant and recessive traits in their school. Their hypothesis was:
There will be more learners with dominant traits than learners with recessive traits.
The traits below were investigated in 200 learners:
DOMINANT TRAIT
RECESSIVE TRAIT
Unattached earlobe
Attached earlobe
Rolled tongue
Unrolled tongue
Bent little finger
Straight little finger
The results below were obtained during the investigation.
NUMBER OF LEARNERS
TRAIT
DOMINANT
RECESSIVE
Earlobe
70
130
Tongue
24
176
Little finger
15
185
4.1.1
4.1.2
4.1.3
4.1.4
4.1.5
4.1.6
Show the results for each trait above as bar graphs on the same system of axes.
Explain why age need NOT be controlled in this investigation.
State ONE way in which the learners ensured reliable results.
State any TWO planning steps that the learners had to consider before conducting the investigation.
Will the learners accept or reject their hypothesis?
Explain your answer to QUESTION 4.1.5.
(8)
(2)
(1)
(2)
(1)
(2)
(16)
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4.2
In mosquitoes there is a gene locus which has alleles involved in resistance to DDT, a well-known insecticide.
The graph below shows the number of mosquitoes and their genotypes collected from 1965 when DDT was first used, until 1970, two years after the spraying of DDT stopped.
4.2.1
4.2.2
4.2.3
4.2.4
How many alleles are involved in the trait for resistance in mosquitoes?
State the genotype for resistance to DDT.
Which genotype appeared most frequently in the population in 1970?
Which genotype's chances of survival were reduced after the spraying of DDT was stopped in 1968?
(1)
(1)
(1)
(1)
(4)
4.3
Charles Darwin and Jean Baptiste de Lamarck had different ideas to explain evolution. Describe how each of them would have explained the evolution of the long necks of giraffes. Justify whose idea is more acceptable in the science community today.
Content:
Synthesis:
(17)
(3)
(20)
NOTE:
NO marks will be awarded for answers in the form of flow charts or diagrams.
TOTAL SECTION C:
GRAND TOTAL:
40
150
Years
Spraying started
Spraying stopped 0102030405060708090100196519661967196819691970
Rr
Number of mosquitoes
RR
rr