This document discusses lichens and their use as bioindicators of environmental quality. Some key points:
- Lichens are a symbiotic organism composed of a fungus and photosynthetic algae or cyanobacteria. They can live in extreme environments and are found worldwide.
- Lichens are good bioindicators because they are long-lived, can absorb environmental pollutants, and their presence/health reflects air quality over long periods of time. Damage to lichens can indicate high levels of pollutants like sulfur dioxide, fluoride, and ammonia.
- The document describes a classroom project where students measure lichen coverage on trees near their school to assess local air quality.
mycorrhiza types, distribution and significance.shabnoorshaikh1
This document discusses the types, distribution, and significance of mycorrhiza. It describes the two main types - endomycorrhiza and ectomycorrhiza - and their subtypes, including vesicular arbuscular mycorrhiza (VAM), ericoid mycorrhiza, and orchid mycorrhiza. It notes that over 90% of land plants form mycorrhizal associations, which involve a three-way interaction between the host plant, fungi, and soil factors. The document also outlines the global distribution of different mycorrhizal types and discusses the agricultural significance of mycorrhizae in improving plant nutrient uptake, tolerance to stress, and soil structure.
Ecosystems can be classified in various ways based on their size and level of human interference. The biosphere is the largest ecosystem encompassing all others. Ecosystems also exist at the mega, marine, freshwater, semi-terrestrial, terrestrial, urban-industrial, macro, meso, and micro levels. Natural ecosystems are self-regulating without human interference, while artificial ecosystems are man-made like cities and croplands. Disturbances, whether abiotic like tsunamis or biotic like insects, disrupt ecosystems. Succession describes how communities change and recover after disturbances through primary succession in new areas and secondary succession in previously inhabited areas.
Cyanobacteria as a Biofertilizer (BY- Ayushi).pptxAyushiKardam
Cyanobacteria, also known as “blue-green algae”.
They are aquatic and photosynthetic, that is, they live in the water, and can manufacture their own food. Because they are bacteria, they are quite small and usually unicellular, though they often grow in colonies large enough to see.
They are the most abundant group of organisms on the earth. They are autotrophic and found in a diverse environment, especially in the marine and freshwater.
This document outlines the 9 major phytogeographical regions of India: 1) Western Himalayas, 2) Eastern Himalayas, 3) Indus Plains, 4) Gangetic Plains, 5) Central India, 6) Deccan, 7) Western Coast of Malabar, 8) Assam, and 9) Bay Islands of Andaman and Nicobar. Each region is characterized by its climate, vegetation, altitude, rainfall, and dominant plant species. The Western Himalayas contain 3 subzones from the shoreline to the snowline dominated by Sal, oaks, and conifers respectively. The Eastern Himalayas also have 3 zones with tropical and temperate forests and alpine
Ecades and ecotype - Ecades•introduction •Definition•Explanation•types of ecades , Ecotype, • introduction, •Definition ,•Ecotype VS. species ,•How did ecotype appear ,•From ecotype to species, •Example
This presentation intends to give a bird's eye view of different abiotic ecological factors with special reference to light, temperature, fire and wind and their impact on ecosystem.
This document provides an overview of mycorrhiza, which is a symbiotic relationship between fungi and plant roots. It defines mycorrhiza and explains that 95% of plant species form these relationships. It then classifies and describes the main types of mycorrhizal associations like ectomycorrhiza, endomycorrhiza, and orchid mycorrhiza. The document outlines the importance and benefits of mycorrhizal relationships for plant growth and health. It also discusses methods for isolating, mass producing, and applying mycorrhizal fungi.
mycorrhiza types, distribution and significance.shabnoorshaikh1
This document discusses the types, distribution, and significance of mycorrhiza. It describes the two main types - endomycorrhiza and ectomycorrhiza - and their subtypes, including vesicular arbuscular mycorrhiza (VAM), ericoid mycorrhiza, and orchid mycorrhiza. It notes that over 90% of land plants form mycorrhizal associations, which involve a three-way interaction between the host plant, fungi, and soil factors. The document also outlines the global distribution of different mycorrhizal types and discusses the agricultural significance of mycorrhizae in improving plant nutrient uptake, tolerance to stress, and soil structure.
Ecosystems can be classified in various ways based on their size and level of human interference. The biosphere is the largest ecosystem encompassing all others. Ecosystems also exist at the mega, marine, freshwater, semi-terrestrial, terrestrial, urban-industrial, macro, meso, and micro levels. Natural ecosystems are self-regulating without human interference, while artificial ecosystems are man-made like cities and croplands. Disturbances, whether abiotic like tsunamis or biotic like insects, disrupt ecosystems. Succession describes how communities change and recover after disturbances through primary succession in new areas and secondary succession in previously inhabited areas.
Cyanobacteria as a Biofertilizer (BY- Ayushi).pptxAyushiKardam
Cyanobacteria, also known as “blue-green algae”.
They are aquatic and photosynthetic, that is, they live in the water, and can manufacture their own food. Because they are bacteria, they are quite small and usually unicellular, though they often grow in colonies large enough to see.
They are the most abundant group of organisms on the earth. They are autotrophic and found in a diverse environment, especially in the marine and freshwater.
This document outlines the 9 major phytogeographical regions of India: 1) Western Himalayas, 2) Eastern Himalayas, 3) Indus Plains, 4) Gangetic Plains, 5) Central India, 6) Deccan, 7) Western Coast of Malabar, 8) Assam, and 9) Bay Islands of Andaman and Nicobar. Each region is characterized by its climate, vegetation, altitude, rainfall, and dominant plant species. The Western Himalayas contain 3 subzones from the shoreline to the snowline dominated by Sal, oaks, and conifers respectively. The Eastern Himalayas also have 3 zones with tropical and temperate forests and alpine
Ecades and ecotype - Ecades•introduction •Definition•Explanation•types of ecades , Ecotype, • introduction, •Definition ,•Ecotype VS. species ,•How did ecotype appear ,•From ecotype to species, •Example
This presentation intends to give a bird's eye view of different abiotic ecological factors with special reference to light, temperature, fire and wind and their impact on ecosystem.
This document provides an overview of mycorrhiza, which is a symbiotic relationship between fungi and plant roots. It defines mycorrhiza and explains that 95% of plant species form these relationships. It then classifies and describes the main types of mycorrhizal associations like ectomycorrhiza, endomycorrhiza, and orchid mycorrhiza. The document outlines the importance and benefits of mycorrhizal relationships for plant growth and health. It also discusses methods for isolating, mass producing, and applying mycorrhizal fungi.
Alpha diversity refers to the mean diversity of species within individual sites or ecosystems at a local scale. It is measured by counting the number of distinct taxa like species, genera, or families within an ecosystem. Alpha diversity, along with beta diversity (diversity between habitats along environmental gradients) and gamma diversity (overall diversity in a region), were concepts introduced by R.H. Whittaker to describe biodiversity at different scales.
This document provides an overview of plant nomenclature and the rules for scientific naming of plants according to the International Code of Nomenclature for algae, fungi, and plants (ICN). It discusses key concepts such as scientific names, binomial nomenclature, types, ranks, valid publication, synonyms, and correct names. The document is intended as an educational guide for those interested in learning about the standards for assigning and determining scientific names of plant taxa.
This document discusses the economical importance of algae. It outlines 12 ways that algae are useful, including as primary producers of oxygen, as a food source, and in producing iodine, antibiotics, fertilizer, and other products. Algae play important roles in sewage disposal, land reclamation, and nitrogen fixation. However, the overgrowth of algae can also negatively impact water quality and harm aquatic organisms. Heavy blooms can deplete oxygen from water and release toxins. Some algal species are also parasitic or can contaminate water supplies and cause human diseases.
Bryophyte is a traditional name used to refer to all embryophytes (land plants) that are non-vascular plants such as mosses, liverworts etc.
The defining feature of bryophytes is that they do not have true vascular tissue. Although some do have specialized tissues for the transport of water, they are not considered to be true vascular tissue since they do not contain lignin.
There are about 25,000 different species of bryophytes in the world today.
Even though these plants are small in size, they are one of the largest groups of land plants and can be found almost everywhere in the world.
1) Bacteria play an important role in soil by decomposing organic matter and recycling nutrients back into the soil. This promotes plant growth.
2) Some bacteria increase soil fertility by fixing atmospheric nitrogen or converting nitrogen into plant-available forms. Nitrogen-fixing bacteria live symbiotically in root nodules of legumes or freely in soil.
3) The nitrogen-fixing, nitrifying, and ammonifying bacteria work together in the nitrogen cycle to transform nitrogen between forms available to plants and the atmosphere. This maintains soil nitrogen levels over time.
1. Lichens are a symbiotic organism consisting of a fungus and an algae or cyanobacteria. They can grow in a wide range of habitats and environments.
2. Lichens have several types of structures and reproduce both sexually through structures like apothecia, and asexually through fragmentation, soredia, and isidia.
3. Lichens serve important ecological roles as pioneer colonizers and environmental pollution indicators. They also have economic uses including as food, medicines, dyes, and in brewing. However, some lichens can be harmful by spreading fires or accumulating radioactive materials.
Spirulina cultivation requires careful handling as the wet biomass is either sun dried or spray-dried for marketing. Drying is important to minimize contamination when consumed by humans. The highly alkaline pH levels during growth also help reduce contamination. References are provided on spirulina culture methods and statistics for fisheries and agriculture.
This document discusses plant conservation and biotechnology. It covers various topics related to biodiversity and conservation, including the importance of biodiversity, causes of biodiversity loss, and methods of conservation both in situ and ex situ. For in situ conservation, it describes different types of protected areas in India such as biosphere reserves, national parks, tiger reserves, and wildlife sanctuaries. For ex situ conservation, it discusses various methods like gene sanctuaries, seed banks, field gene banks, and tissue culture storage. The overall document provides an overview of biodiversity conservation approaches and the role of biotechnology in plant conservation.
This document summarizes key concepts about the absorption spectrum, action spectrum, and two photosystems in plant photosynthesis. It explains that chlorophyll a absorbs mainly in the blue and red regions of the light spectrum. The effectiveness of different light wavelengths in photosynthetic processes like CO2 fixation is known as the action spectrum. The rate of photosynthesis declines sharply after 680nm, known as the red drop phenomenon, but combining 680nm and 700nm light results in higher photosynthesis than individually. This led to the conclusion that there are two photosystems - PSI which uses 700nm light and PSII which uses 680nm light, and they work cooperatively during photosynthesis.
Azolla is an aquatic fern that forms a symbiotic relationship with the cyanobacterium Anabaena azollae. Anabaena azollae lives within cavities in Azolla's leaves and is able to fix atmospheric nitrogen, which it shares with the plant. This association increases the nitrogen-fixing ability of Anabaena azollae. Azolla-Anabaena mats can be used as green manure for agriculture, improving soil fertility and reducing the need for chemical fertilizers.
In this presentation, concept of xerophytes, types of xerophytes and adaptations (morphological, anatomical and physiological) developed in them are explained.
Numerical taxonomy is a classification system that uses numerical methods to group taxonomic units based on their character states. It was developed in the 1950s alongside multivariate analysis and computer development. Numerical taxonomy aims to define homogeneous clusters of organisms by integrating different data types through statistical analysis. This results in a phenogram or dendrogram that illustrates the relationships between taxa based on their similarities. Numerical taxonomy is useful for studying relationships between bacteria and other microorganisms.
The document summarizes the types and positions of sori (clusters of sporangia) in ferns. There are three main types of sori: simplices where all sporangia mature simultaneously; gradatae where sporangia mature basipetally from distal to proximal ends; and mixtae which are a mixed aggregation of young and old sporangia. Sori can be marginal, ventral, or borne within structures like sporocarps. Some sori have an indusium or scale for protection, and these can have reniform, circular, funnel-shaped or other morphologies.
This document discusses the taxonomic hierarchy used for classifying organisms, specifically angiosperms. It explains that taxonomic hierarchy arranges organisms into successive levels from kingdom down to species. The main levels are kingdom, division, class, order, family, genus, and species. Major categories include division, class, and order, while minor categories are genus and species. The hierarchy allows grouping of organisms based on their diversity and helps classify plants into appropriate groups.
The document discusses host-parasite relationships and the mechanisms of plant infection. It covers:
1. How fungi obtain food from host plants through haustoria and establish close connections.
2. The definition of host and parasite. Host-parasite relationships affect each other's growth and metabolism.
3. The mechanisms of infection include spores contacting hosts, germ tubes attaching and penetrating tissues using enzymes, and hyphae entering and spreading within host tissues. Pathogens can enter through natural openings or wounds.
Major firewood and timber yielding plantsram krishan
The document summarizes several major firewood and timber yielding plants found in Jammu and Kashmir, India. It provides the botanical name, common name, family, description, and uses for 18 different plants. Some of the key species discussed include Tectona grandis (teak), used widely for furniture making; Dalbergia sisso (Indian rosewood) used for construction, musical instruments and furniture; and Shorea robusta (sal tree) which provides a hard and durable wood used locally as a fuel source.
Phytogeography, climate, vegetation and botanical zonesEmaSushan
This document discusses the key concepts and principles of phytogeography, which is the study of the geographic distribution of plants. It covers definitions of phytogeography, the major divisions of descriptive and interpretive phytogeography, principles related to plant environment, plant responses, migration of floras and climaxes, and perpetuation and evolution of floras. Factors affecting species distribution include geological history, migration, and ecological amplitude. The distribution of plants is primarily controlled by climate, soils, and biotic interactions, and each species has a defined range of environmental tolerances.
Carbon is the major constituent element in plants after water. It is found in important biomolecules like chlorophyll, cytochromes, alkaloids, and many vitamins. Nitrogen plays an important role in plant metabolism, growth, reproduction and heredity. Plants cannot utilize atmospheric nitrogen directly and require nitrogen-fixing bacteria to convert it into bioavailable forms like nitrates, nitrites and ammonia. Nitrogen fixation can occur through both biological and non-biological means, with biological nitrogen fixation involving symbiotic associations between plants and nitrogen-fixing microorganisms like Rhizobium bacteria.
This document discusses nitrogen fixation, which is the process of converting atmospheric nitrogen into ammonia. It is important because most organisms cannot use atmospheric nitrogen. The conversion is typically done by bacteria or cyanobacteria through one of two processes: symbiotic or non-symbiotic fixation. Symbiotic fixation often involves root nodules formed via infection by Rhizobia bacteria in legumes and some non-legumes. This process allows for nitrogen fixation to occur inside the plant.
Chap 5 fungi and other organism (mutualistic)Alia Najiha
1) Fungi can have mutualistic or parasitic relationships with other organisms. Mutualistic relationships include mycorrhizal associations between fungi and plant roots that benefit both organisms.
2) Lichens are a mutualism between a fungus and an alga or cyanobacterium. The alga provides carbohydrates while the fungus provides minerals and structure.
3) Fungi play important ecological roles through mycorrhizal and lichen relationships and can be used as indicators of air pollution.
Lichens , types of lichens based on growth and habitat, importance of lichens, fungal habits and colonization strategies, Air borne fungi and micotoxins.
Alpha diversity refers to the mean diversity of species within individual sites or ecosystems at a local scale. It is measured by counting the number of distinct taxa like species, genera, or families within an ecosystem. Alpha diversity, along with beta diversity (diversity between habitats along environmental gradients) and gamma diversity (overall diversity in a region), were concepts introduced by R.H. Whittaker to describe biodiversity at different scales.
This document provides an overview of plant nomenclature and the rules for scientific naming of plants according to the International Code of Nomenclature for algae, fungi, and plants (ICN). It discusses key concepts such as scientific names, binomial nomenclature, types, ranks, valid publication, synonyms, and correct names. The document is intended as an educational guide for those interested in learning about the standards for assigning and determining scientific names of plant taxa.
This document discusses the economical importance of algae. It outlines 12 ways that algae are useful, including as primary producers of oxygen, as a food source, and in producing iodine, antibiotics, fertilizer, and other products. Algae play important roles in sewage disposal, land reclamation, and nitrogen fixation. However, the overgrowth of algae can also negatively impact water quality and harm aquatic organisms. Heavy blooms can deplete oxygen from water and release toxins. Some algal species are also parasitic or can contaminate water supplies and cause human diseases.
Bryophyte is a traditional name used to refer to all embryophytes (land plants) that are non-vascular plants such as mosses, liverworts etc.
The defining feature of bryophytes is that they do not have true vascular tissue. Although some do have specialized tissues for the transport of water, they are not considered to be true vascular tissue since they do not contain lignin.
There are about 25,000 different species of bryophytes in the world today.
Even though these plants are small in size, they are one of the largest groups of land plants and can be found almost everywhere in the world.
1) Bacteria play an important role in soil by decomposing organic matter and recycling nutrients back into the soil. This promotes plant growth.
2) Some bacteria increase soil fertility by fixing atmospheric nitrogen or converting nitrogen into plant-available forms. Nitrogen-fixing bacteria live symbiotically in root nodules of legumes or freely in soil.
3) The nitrogen-fixing, nitrifying, and ammonifying bacteria work together in the nitrogen cycle to transform nitrogen between forms available to plants and the atmosphere. This maintains soil nitrogen levels over time.
1. Lichens are a symbiotic organism consisting of a fungus and an algae or cyanobacteria. They can grow in a wide range of habitats and environments.
2. Lichens have several types of structures and reproduce both sexually through structures like apothecia, and asexually through fragmentation, soredia, and isidia.
3. Lichens serve important ecological roles as pioneer colonizers and environmental pollution indicators. They also have economic uses including as food, medicines, dyes, and in brewing. However, some lichens can be harmful by spreading fires or accumulating radioactive materials.
Spirulina cultivation requires careful handling as the wet biomass is either sun dried or spray-dried for marketing. Drying is important to minimize contamination when consumed by humans. The highly alkaline pH levels during growth also help reduce contamination. References are provided on spirulina culture methods and statistics for fisheries and agriculture.
This document discusses plant conservation and biotechnology. It covers various topics related to biodiversity and conservation, including the importance of biodiversity, causes of biodiversity loss, and methods of conservation both in situ and ex situ. For in situ conservation, it describes different types of protected areas in India such as biosphere reserves, national parks, tiger reserves, and wildlife sanctuaries. For ex situ conservation, it discusses various methods like gene sanctuaries, seed banks, field gene banks, and tissue culture storage. The overall document provides an overview of biodiversity conservation approaches and the role of biotechnology in plant conservation.
This document summarizes key concepts about the absorption spectrum, action spectrum, and two photosystems in plant photosynthesis. It explains that chlorophyll a absorbs mainly in the blue and red regions of the light spectrum. The effectiveness of different light wavelengths in photosynthetic processes like CO2 fixation is known as the action spectrum. The rate of photosynthesis declines sharply after 680nm, known as the red drop phenomenon, but combining 680nm and 700nm light results in higher photosynthesis than individually. This led to the conclusion that there are two photosystems - PSI which uses 700nm light and PSII which uses 680nm light, and they work cooperatively during photosynthesis.
Azolla is an aquatic fern that forms a symbiotic relationship with the cyanobacterium Anabaena azollae. Anabaena azollae lives within cavities in Azolla's leaves and is able to fix atmospheric nitrogen, which it shares with the plant. This association increases the nitrogen-fixing ability of Anabaena azollae. Azolla-Anabaena mats can be used as green manure for agriculture, improving soil fertility and reducing the need for chemical fertilizers.
In this presentation, concept of xerophytes, types of xerophytes and adaptations (morphological, anatomical and physiological) developed in them are explained.
Numerical taxonomy is a classification system that uses numerical methods to group taxonomic units based on their character states. It was developed in the 1950s alongside multivariate analysis and computer development. Numerical taxonomy aims to define homogeneous clusters of organisms by integrating different data types through statistical analysis. This results in a phenogram or dendrogram that illustrates the relationships between taxa based on their similarities. Numerical taxonomy is useful for studying relationships between bacteria and other microorganisms.
The document summarizes the types and positions of sori (clusters of sporangia) in ferns. There are three main types of sori: simplices where all sporangia mature simultaneously; gradatae where sporangia mature basipetally from distal to proximal ends; and mixtae which are a mixed aggregation of young and old sporangia. Sori can be marginal, ventral, or borne within structures like sporocarps. Some sori have an indusium or scale for protection, and these can have reniform, circular, funnel-shaped or other morphologies.
This document discusses the taxonomic hierarchy used for classifying organisms, specifically angiosperms. It explains that taxonomic hierarchy arranges organisms into successive levels from kingdom down to species. The main levels are kingdom, division, class, order, family, genus, and species. Major categories include division, class, and order, while minor categories are genus and species. The hierarchy allows grouping of organisms based on their diversity and helps classify plants into appropriate groups.
The document discusses host-parasite relationships and the mechanisms of plant infection. It covers:
1. How fungi obtain food from host plants through haustoria and establish close connections.
2. The definition of host and parasite. Host-parasite relationships affect each other's growth and metabolism.
3. The mechanisms of infection include spores contacting hosts, germ tubes attaching and penetrating tissues using enzymes, and hyphae entering and spreading within host tissues. Pathogens can enter through natural openings or wounds.
Major firewood and timber yielding plantsram krishan
The document summarizes several major firewood and timber yielding plants found in Jammu and Kashmir, India. It provides the botanical name, common name, family, description, and uses for 18 different plants. Some of the key species discussed include Tectona grandis (teak), used widely for furniture making; Dalbergia sisso (Indian rosewood) used for construction, musical instruments and furniture; and Shorea robusta (sal tree) which provides a hard and durable wood used locally as a fuel source.
Phytogeography, climate, vegetation and botanical zonesEmaSushan
This document discusses the key concepts and principles of phytogeography, which is the study of the geographic distribution of plants. It covers definitions of phytogeography, the major divisions of descriptive and interpretive phytogeography, principles related to plant environment, plant responses, migration of floras and climaxes, and perpetuation and evolution of floras. Factors affecting species distribution include geological history, migration, and ecological amplitude. The distribution of plants is primarily controlled by climate, soils, and biotic interactions, and each species has a defined range of environmental tolerances.
Carbon is the major constituent element in plants after water. It is found in important biomolecules like chlorophyll, cytochromes, alkaloids, and many vitamins. Nitrogen plays an important role in plant metabolism, growth, reproduction and heredity. Plants cannot utilize atmospheric nitrogen directly and require nitrogen-fixing bacteria to convert it into bioavailable forms like nitrates, nitrites and ammonia. Nitrogen fixation can occur through both biological and non-biological means, with biological nitrogen fixation involving symbiotic associations between plants and nitrogen-fixing microorganisms like Rhizobium bacteria.
This document discusses nitrogen fixation, which is the process of converting atmospheric nitrogen into ammonia. It is important because most organisms cannot use atmospheric nitrogen. The conversion is typically done by bacteria or cyanobacteria through one of two processes: symbiotic or non-symbiotic fixation. Symbiotic fixation often involves root nodules formed via infection by Rhizobia bacteria in legumes and some non-legumes. This process allows for nitrogen fixation to occur inside the plant.
Chap 5 fungi and other organism (mutualistic)Alia Najiha
1) Fungi can have mutualistic or parasitic relationships with other organisms. Mutualistic relationships include mycorrhizal associations between fungi and plant roots that benefit both organisms.
2) Lichens are a mutualism between a fungus and an alga or cyanobacterium. The alga provides carbohydrates while the fungus provides minerals and structure.
3) Fungi play important ecological roles through mycorrhizal and lichen relationships and can be used as indicators of air pollution.
Lichens , types of lichens based on growth and habitat, importance of lichens, fungal habits and colonization strategies, Air borne fungi and micotoxins.
Fungi play several important ecological roles. As decomposers, they break down dead organic matter and release nutrients back into the soil, recycling them for other organisms. As mycorrhizal partners with plants, fungi help plants absorb water and minerals in exchange for carbohydrates. Lichens, which consist of fungi and algae, are pioneers in plant succession and weather rocks into soil. Some fungi also help bioremediate polluted environments and produce antibiotics. However, some fungi can also cause diseases or destroy plants, wood, food, and other materials.
Lichens are symbiotic associations between fungi and algae or cyanobacteria. The fungus provides shelter and nutrients to the photosynthetic partner in exchange for food. Lichens can reproduce sexually through fungal structures or asexually by fragmentation or dispersal of soredia and isidia. They are found worldwide in diverse environments and have various ecological roles including nitrogen fixation and pollution monitoring.
Lichens=(Algae+Fungi) Symbiotic Association (Phycobiont+ Mycobiont), Idealistic marriage, Pioneers species of Xerosere succession Shows Dual Nature, Trinity=(One Algae+Two Fungi), Natural farmers, it melt stone convert stone to soil particles
Lichens are a symbiotic partnership between a fungus and a photosynthetic symbiont such as an alga or cyanobacterium. This relationship results in a stable structure called a thallus. Lichens can grow in a wide range of habitats and withstand environmental extremes. They are primary colonizers and play an important role in weathering rock and forming soil. Lichens are very sensitive to air pollution. Their fungal partners are typically ascomycetes which produce spores. Lichens reproduce through vegetative fragmentation or sexually through spores. They exist in crustose, foliose, fruticose or other forms depending on their structure and growth.
This document provides an overview of lichens. It begins with definitions, describing lichens as a symbiotic association between fungi and algae or cyanobacteria. It then covers the history of lichen research, habitats of lichens, ways of classifying lichens, their structure and reproduction methods. The document discusses lichens' economic importance, including as a food source, in medicine, dye production, and their use as bioindicators of environmental pollution. It concludes with an explanation of lichenometry, which uses lichen growth rates to determine the age of exposed rocks.
Lichens are the symbiotic associated organisms which forms the association between fungus and photosynthetic substances. Their aqueous extract produce vast number of secondary metabolites with varying biological activities including antibiotic, anti-mycobacterial, antiviral, anti-inflammatory, anti-proliferative and cytotoxic effects against various diseases. Lichens can be of following types : Based on the substrate of growing. 01) Corticolous (grows on tree barks), 02) Follicolous (grows on leaves surfaces), 03) Saxicolous (grows on rock surfaces), 04) Terricolous (grows on soil) 05)Musicolous (grows on mosses)
The document defines key terms related to ecosystem structures and population interactions. It distinguishes between biotic (living) and abiotic (non-living) components of ecosystems. Trophic levels including producers, primary consumers, secondary consumers, and decomposers are explained. Pyramids of numbers, biomass and productivity are defined. Species, populations, habitats, niches, communities, and ecosystems are defined using local examples. Population interactions such as mutualism, parasitism, predation, herbivory and competition are described through examples.
The document discusses microbial ecology and the composition of soil as an environment for microorganisms. It notes that soil is a complex ecosystem containing a vast array of microbes, plants, and animals. The lithosphere is composed of weathered rock, humus, and nutrients. The rhizosphere around plant roots contains associated bacteria, fungi, and protozoa. Microbes play important roles in soil, including nutrient provision, decomposition, nitrogen fixation, and preventing pathogens. Bacteria, actinomycetes, and fungi are the dominant microbial groups in soil and influence processes like nutrient cycling and plant growth.
Ecology is the study of interactions between living organisms and their environment. It examines both biotic factors like plants, animals, and microorganisms, as well as abiotic factors such as sunlight, water, and soil. Ecology views environments holistically and studies the complex relationships within and between populations in an ecosystem. Organisms depend on each other through food webs, with plants and algae as primary producers, herbivores and omnivores as primary consumers, and carnivores and decomposers recycling nutrients and matter. Ecology analyzes these interactions across different levels of organization from organisms and populations to communities, ecosystems, and the global biosphere.
Biological Classification, CH-2 of Class-XI.
Dear students
I have prepared the ppt based on NCERT, as per your requirement. Its full of images, examples, activities and also i have attached one worksheet with it. Hope you like it.
This document provides information about a second edition of a pictorial atlas of soil and seed fungi. It includes prefaces from the original Japanese edition and the translated English edition. It describes the contents of the book, which contains descriptions, illustrations and photographs of over 350 fungal species isolated from soil and plant materials. It also outlines the methodology used for collecting and identifying the fungal isolates.
This document provides information about a second edition of a pictorial atlas of soil and seed fungi. It includes prefaces from the original Japanese edition and the translated English edition. It describes the contents of the book, which contains descriptions, illustrations and photographs of over 350 fungal species isolated from soil and plant materials. It also outlines the methodology used for collecting and identifying the fungal isolates.
This document provides prefaces to the second edition and English edition of a book titled "Pictorial Atlas of Soil and Seed Fungi". The book contains photographs and descriptions of 308 fungal species isolated from soil and seeds. It has been revised to include additional fungal species and updated classification information. The prefaces discuss the importance of studying soil fungi and their role in ecosystems, as well as the lack of resources on the morphology of soil and seed fungi. The book aims to increase knowledge and interest in these often overlooked fungi.
The document summarizes the key organic macromolecules found in living organisms:
Carbohydrates provide energy and structure, with monomers like glucose and polymers like starch. Lipids store energy and provide insulation, composed of glycerol and fatty acids. Proteins build cell structures and control functions, made of amino acid monomers. Nucleic acids store and transfer genetic information as DNA and RNA. The document then discusses testing methods for identifying these four major macromolecule types.
Plant microbe interaction by dr. ashwin chekeAshwin Cheke
PLANT MICROBE – INTERACTIONS AND THEIR MUTUAL BENEFITS IN ENHANCING SOIL HEALTH AND AGRICULTURAL PRODUCTION ,
IT ALSO INCREASE CROP PRODUCTIVITY AND IMPROVE SOIL HEALTH
This document provides an overview of microbiology and microbial nutrition and growth. It defines microbiology as the study of microorganisms including bacteria, archaea, algae, fungi, protozoa and viruses. It describes how microbes play important roles in various environments and human life. It then discusses the major groups of microorganisms and their characteristics. Finally, it covers microbial nutrition, growth conditions and factors that influence growth.
The document discusses microbial diversity and ecology in marine environments. It examines the candidate order Woeseiales, a group of Gammaproteobacteria that accounts for 1-22% of sequences retrieved from marine sediment surveys. The order is widely distributed in seafloor communities but little is known about its ecology. The study characterized the phylogeny, distribution patterns, abundance, and metabolic potential of Woeseiales bacteria from deep sea sediments. It found lineages more prevalent in deep sea than coastal environments. Cell counts showed Woeseiales account for 5% of microbial cells in deep sea surface sediments. Comparative analyses suggested members likely grow on proteinaceous matter derived from detrital cell remnants in marine sediments.
The document discusses applications of DNA technology including the Human Genome Project. The Human Genome Project was a 13-year international project completed in 2003 that mapped and sequenced the entire human genome. Its goals were to identify all human genes, determine the sequence of DNA's 3 billion base pairs, store this information in databases, improve analysis tools, and address ethical issues arising from the research. The project used genetic mapping, physical mapping, and DNA sequencing approaches.
This document provides a summary of Nepal's State of the Environment Report from 2000. Some key points:
- Population growth and unsustainable use of natural resources have contributed to major environmental problems like land degradation, deforestation, and pollution.
- Only 30% of the population has access to piped water and only 7% has sanitation facilities. Water quality is degrading.
- Forest cover has declined significantly though community forestry programs have helped. Biodiversity faces threats from habitat loss.
- Solid waste is a major problem in cities and hazardous waste disposal needs improvement. Air pollution, especially from vehicles, is a concern in urban areas.
- Agriculture has increased but yields remain
New Record Of Fleshy Fungi From Khumbu Region, Nepalkiran
1) A new species of fleshy fungi, Pulverboletus ravenelii, was recently collected in Ghat, Nepal at an altitude of 2604 meters.
2) P. ravenelii is classified in the class Basidiomycetes and was found growing under coniferous forest dominated by Pinus wallichiana.
3) This represents the first record of P. ravenelii in Nepal.
Floral Diversity In Wetlands Of Nepal In Terai Region Of Nepalkiran
This article provides an overview of floral diversity in the wetlands of Nepal's Terai region. It finds that the Terai contains 720 species of vascular plants, including 23 pteridophytes, 2 gymnosperms, 469 dicots and 226 monocots. The Koshi Tappu and Ghodaghodi wetlands contain 670 and 473 species respectively. Many plant species in the Terai wetlands are economically important or endemic. However, the wetlands face threats from habitat loss and invasive alien species.
This document describes 36 taxa of desmids belonging to 7 genera that were identified from Bees-hazaar Lake in Chitwan, Nepal. Eleven of the taxa are reported for the first time in Nepal. The desmids were collected from five sites around the lake from June to September 2007. The taxa identified, their morphological characteristics, and known distributions are described. This work contributes to expanding the knowledge of desmid diversity in Nepal.
Wild edible fungi collection contributes significantly to livelihoods in rural Nepal and neighboring countries. In Nepal, morels are the main exported fungi, though over 50 species are consumed locally. Neighboring countries like China and Tibet rely heavily on fungi collection for rural incomes. While Nepal has potential to increase exports and domestic trade of other fungi, quality control, training, and sustainable management practices need to be established first to fully realize economic benefits and ensure resource protection.
Andrewsianthus ferrugineus is an endangered species of liverwort endemic to the Himalayas. It grows on tree trunks and rocks in alpine forests and scrublands between 2440-4075 meters in Central Nepal, East Nepal, Sikkim, and Bhutan. The small red-brown plant is dioecious with fragile leafy stems and lobed leaves. Its habitat in the alpine region is threatened by overgrazing, forest clearing, burning, and fuel wood collection.
A Comparison Of Species Rchness Of Bryophytes In Nepal, Central Nepalkiran
This document summarizes a study comparing altitudinal species richness patterns of bryophytes (liverworts and mosses) in Nepal to patterns observed in ferns and flowering plants. The study uses published data on the altitudinal ranges of over 840 Nepalese bryophyte species to estimate species richness in 100m elevation bands from 100-5500m. Generalized additive models show bryophytes have a unimodal relationship between richness and elevation, with liverworts peaking at 2800m and mosses at 2500m, contrasting with ferns peaking at 1900m and vascular plants from 1500-2500m. Endemic liverwort richness peaks higher than non-endemics.
Optimal Defence Theory And Secondary Chemistrykiran
This study examined variation in glucosinolate content between leaves and petals of wild radish (Raphanus sativus) to test predictions of optimal defence theory. The theory predicts that tissues most important for fitness, like reproductive parts, will be constitutively more defended. The study found that petals had higher constitutive glucosinolate levels than leaves, supporting the prediction. However, individual glucosinolates differed in their degree of inducibility between tissues. Petal colour variants also differed in their induced responses but not constitutive levels. The results provide evidence that selection from pollinators and herbivores could maintain variation in defence chemistry and petal colour in wild radish.
Nepal has many globally significant wetland ecosystems that provide ecological, economic, cultural, and recreational value. However, wetlands are being degraded and destroyed by natural succession, pollution, dams, overexploitation, siltation, and population growth. A lack of awareness, effective policy, responsible institutions, and clear ownership has exacerbated these threats. A conservation plan is needed to protect wetlands through stronger national support, protected area management, conservation of unprotected wetlands, and clear institutional roles for wetland governance.
Genetic engineering involves isolating and moving genes within and between species using recombinant DNA techniques. This involves using restriction enzymes to cut DNA at specific sequences, and DNA ligase to join DNA fragments. Genes can be cloned by inserting DNA fragments into plasmids or viruses, which are then used to transform host cells. The transformed cells are cultured to produce multiple copies of the gene of interest. Genetic engineering has applications in medicine, agriculture, and industry such as producing therapeutic proteins, engineering pest-resistant crops, and creating transgenic organisms.
B I O T E C H N O L O G Y A N D G E N E T I C E N G E N E E R I N Gkiran
Biotechnology uses techniques such as genetic engineering and cloning to modify organisms or their genes for useful applications like producing therapeutic proteins, developing genetically engineered vaccines, and creating transgenic plants with desirable traits. Techniques include transferring genes between organisms using vectors like plasmids or viruses, screening libraries of cloned DNA to find genes of interest, and using polymerase chain reaction to amplify specific DNA sequences. While biotechnology has potential benefits, it also faces controversies regarding long term safety and environmental impacts of genetically modified organisms.
The document discusses applications of DNA technology including the Human Genome Project. The Human Genome Project was a 13-year international project completed in 2003 that mapped and sequenced the entire human genome. Its goals were to identify all human genes, determine the sequence of DNA's 3 billion base pairs, store this information in databases, improve analysis tools, and address ethical issues arising from the research. The project used genetic mapping, physical mapping, and DNA sequencing approaches.
1. Lichens as Bioindicators
October 2003, p. 16-19 Printer-friendly version
Feature
Lichens as Bioindicators
Gregory L. Smith and Thomas R. Baker
Lichens, small and unobtrusive organisms, are
seldom noticed as they cling to rocks, trees, and
soil in fragile veils or crusts of splendid color and
ornate textures. Their beauty is captivating and
fascinating, and their purpose and origins are
thought-provoking. Lichens are actually two organisms, a fungus and photosynthetic
algae, sharing symbiosis. In a lichen, fungus provides shelter, protection, and water
to the photosynthetic partner who, in turn, provides nutrients to the fungus. The
photosynthetic partner in lichen can be composed of blue-green algae, yellow-green
algae, or cyanobacteria living in relative harmony with many different kinds of fungi.
Lichens are found across the world and are environmentally tolerant organisms,
living in a wide range of habitats, often thriving in the most extreme locations, such
as the arctic tundra. People use them for a great many purposes, including dyes and
medicines in Native American cultures (Brodo, Sharnoff, and Sharnoff 2001), teas
and foodstuffs, as well as fixatives in the manufacturing process of perfumes (USDA
2002).
While lichens are taxonomically classified based on the fungal component, they are
frequently categorized into four morphological (shape) types:
q Crustose—a crust-like lichen growing flat on the substrate
q Foliose—a leafy lichen
q Squamulose—similar to the crustose but often appears as a colony of small
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2. Lichens as Bioindicators
cups with lobes raised
q Fruticose—the most delicate and slow growing. Often appears like hairs
hanging from tree branches or tube-like structures.
Lichens make particularly good bioindicators. Bioindicators are living organisms that
reflect environmental health and quality. A common example of a bioindicator is the
use of canaries by early coal miners to detect suitable air quality underground. While
a caged canary showed signs of activity (e.g. singing), miners were assured that air
quality was relatively good, lacking deadly levels of methane. As the small birds were
much less tolerant of such noxious gases, a canary’s death was a miner’s sure sign to
immediately evacuate. Unlike canaries, lichens are present throughout the world, live
a very long time, and can retain certain environmental pollutants and heavy metals
(Purvis 2000). Such qualities make the use of lichens ideal for classroom science.
Unlike other protocols that use mechanical or chemical indicators with a single
sampling event, many bioindicators have the advantages of long-term monitors and
can therefore span temporal or spatial boundaries that would otherwise pose great
difficulty. Lichens are bioindicators of sulfur dioxide (S02), fluoride, and ammonia.
The effect of these pollutants may be observed on the distribution and diversity of
lichens in your area. As with many bioindicators, lichen damage patterns alone
cannot establish a totally causal link to atmospheric quality, but they can lead
students in a systemic approach to studying the world without great financial cost,
while simultaneously investigating general processes of science, atmospheric quality,
and lichen biology.
Students using lichens as bioindicators
Based on the Standards, we organized a two-week unit allowing students to
investigate their local air quality using lichen from oak trees in and around our town.
Using the collaborative PathFinder Science website (www. pathfinderscience.net/
so2), we were able to construct a unit allowing students to gather background
information, collect and analyze data, and summarily draw conclusions based on
their data.
The PathFinder Science website is a virtual community dedicated to learning about
the material world through science. This collaborative research group grew from an
attempt to fulfill the National Science Education Standards (NRC 1996), the
Benchmarks for Science Literacy (AAAS), and the Kansas Science Education
Standards’ vision for “Science for All Americans” and the process of “doing science.”
PathFinder Science includes many research areas that span numerous science and
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3. Lichens as Bioindicators
mathematics topics. Teachers and students from 21 countries are members of this
research-sharing community that now involves over 1,000 registered classrooms. In
order to become an active member of the community, your classroom must be
registered. There is no cost for registration, but you must fill out a simple online form
to be a part of the group, upload collaborative project data, or publish student
research work. For the lichen project, the website contains guidelines for data
gathering, data sharing, ideas for further research, and more.
Working in cooperative groups of two or three, we first asked students to measure
lichen coverage of trees on and near school property. Guidelines for data collection
include:
q As a class, select a tree species that is readily available throughout the area.
Each cooperative team will need a single mature tree to sample. In order to
mark the tree for later identification, tie a string around the trunk 1.5 meters
above the ground. Include a cooperative team name and class period label
attached to the string.
q Using a USGS topographic map or Global Positioning Satellite Unit determine
the latitude and longitude of your samples and record on the data collection
table (see Figure 1). As an alternative, use trees that are within one kilometer
(0.6 mile) of your school and record the latitude and longitude of your school
site on the data collection table.
q Try to choose trees with alkaline bark, preferably ash, then elm or sycamore. If
need be, use trees with a more acidic bark, preferably oak, then beech or birch.
To test the acidity of the bark, scrape a small amount of bark from a sample
tree into distilled water and let it soak. After 24 hours, measure the pH.
A standardized grid from PathFinder Science (see Resources), printed on a
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4. Lichens as Bioindicators
transparency or an acetate sheet, is used to count lichen coverage. The grid is an
arrangement of 100 small hollow circles, placed in a 10-circle by 10-circle format.
Students hold the grid against the side of the tree and count the substrate or
organism present in each of the 100 small circles. For students in many regions, this
count usually results in a number for bare bark, moss, and one or two lichen
morphologies. This process was repeated four times for the tree, in each of the
cardinal directions as determined using a compass. Averaging the results from each
of the four sides provides an index for the tree that we called the Average Lichen
Coverage (ALC). For example, one student group’s ALC index included: 60 percent
bare bark, 15 percent crustose lichen, 10 percent moss, and 5 percent foliose lichen,
etc. On a slightly more pragmatic note, due to the multiple steps required in data
gathering, some students found this process initially difficult but, using cooperative
learning, stronger students were able to support others in their group so the
collection could be completed.
As the lichen “growing season” is typically during the winter months after the leaves
have fallen, this is the best time to measure coverage (or change in coverage). We
found that, when completing such outdoor activities during a cold time of the year,
students were very apt to stay on task so that they could return indoors as soon as
possible. Similarly, outdoor activities during the colder winter months minimize
allergy conflicts and run-ins with poison ivy and poison oak. The only safety issue
during outdoor data collection at school was crossing city streets to get to adjoining
school and community properties.
By itself, the ALC for one tree is fairly meaningless, as the protocol requires several
data points across a geographic region allowing for relative comparisons of data. In
short, the more trees that are sampled, the more accurate a depiction can be
constructed. After collecting the ALC data in class, students were then assigned to
collect the ALC for one tree at home, perferably from the same species of tree. The
following day in class, we had a very good distribution of ALC values from across the
town. To make better sense of their collected data, students then compared their
findings to other students and classes. As a way of organizing data, all students wrote
their home ALC values on a single transparency which was then viewed by the entire
class. In most cases, teachers guided students’ attention to the overhead and
everyone calculated averages (for example: bare bark, moss, crustose lichen, and
foliose lichen columns). By calculating an arithmetic mean, students had an easy way
to compare their data. Students were also directed to note the highest and lowest
value in each column. Inevitably, a student would report excessively high or low
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5. Lichens as Bioindicators
values for a column, leading to a barrage of questions and conjectures about the
variation in the data set.
As geography matters in this study, the location of sampling events is critical to
understanding the local air quality. Using maps freely available from the town’s travel
and tourism board, each student mapped sampling locations from all students in the
class, color coding data points that fell above the class average in blue and data points
that fell below the class average in red. (We’ve found that small blue or red stickers
worked quite well, allowing for relocation of sampling points as needed.) As the data
appeared on the map, the base data (such as streets, railroads, airports, power plants,
and factories) were correlated to the student data.
As students began looking for visual patterns in their data, a number of questions and
contentions began to arise. Often, when the map lacked the location of a facility,
students would draw it in, noting the potential effects it may have on data. As
automobile exhaust is a primary contributor to the atmospheric pollutants in
question, students also began wondering aloud whether all roads should be
considered with the same potential for atmospheric pollutions. Noting that nearby
highways had substantially more vehicles than the smaller county roads on the
opposite side of town, it was decided that all roads could not be treated equally in this
study. Students also concluded that the density of roads signs and stoplights might
also be a valuable consideration, as traffic would tend to concentrate at these points
throughout town. The more data that appeared on each student’s map, the more
questions each student seemed to vocalize. “What if” scenarios and new research
ideas abounded, most legitimately based on the data points students had mapped. To
further guide student use of the map as an analytical tool, we provided five major
themes in which questions and discussions were directed (Mitchell 1999):
1. Where are sampling events and areas of interest located? Based on our research
questions, what features and data are necessary to map?
2. Map the high and low values of data. Do the highest lichen values exist in a
particular part of town? Are the lowest values clustered or spread? Are the high and
low lichen coverage values close or far apart?
3. Where is the greatest density of sampling points (providing more accuracy). Where
is the least dense area? This is a good way to introduce uncertainty into the scientific
research process.
4. What regions or boundaries do the sampling points fall within? Determining
regions is a criteria-based process, typically tied to previous knowledge on the
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6. Lichens as Bioindicators
subject. In the case of lichens, we might ask where and what the bounding regions are
that contribute to the development of atmospheric pollutants. Does the town have an
urban core, industrial complex, or series of highways that could affect regional
atmospheric pollutants from cars or industrial processes? Are lichen coverages
typically higher or lower in regions deemed as agricultural or rural in nature?
5. What is nearby the sampling location? How far is the nearest airport or highway
from your sampling point? Are changes in lichen coverage apparent between your
point and another feature? Is a sampling point too close or too far away to provide
reliable data? Is proximity confounding your data or lending strength to it?
Together the tools of math and geography allow students to gain a good deal of
insight into the relative air quality patterns that exist in their town. The use of paper
mapping or Geographic Information Systems, and digital mapping systems that
easily allow the incorporation of field data, helped our students visualize the trend of
increasingly better air quality as one moves away from town—a realization that
otherwise would not have been possible (see the October 2000 issue of The Science
Teacher in the online archives for information on GIS). Furthermore, students can
readily incorporate the locations of suspected pollutants and, with the aid of the GIS,
determine whether lichen coverage is statistically less in suspected regions.
Collaborative research
Because this was the first time we engaged students in a study of atmospheric quality,
it seemed best to work within a pre-existing, structured framework. The PathFinder
Science website allowed students to upload collected data and retrieve class-wide
data sets already formatted in a spreadsheet. Because the protocol establishes a
relative indicator of atmospheric air quality, it is important to have a large data set.
With the aid of the PathFinder Science network, we were able to compare student
results to other schools in the county and city, that had previously participated in the
study. This large, multi-school data set helped us to create a better context for our
data, essentially extending the meaning of the data our students collected by
providing a basis for comparison and analysis. This makes for an extremely rich
learning environment, encouraging students to ask and begin to answer reasonable
questions related to the geographic, mathematic, or scientific rationale for various
data trends, irregularities, or skeptical observations.
Conclusions
The use of the lichen study at the middle school level is developmentally and
scientifically appropriate. Many young students are idealistic and want to have a
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7. Lichens as Bioindicators
positive impact on their communities and to know how they are connected to the
world around them. Students at this age require explorations that challenge them to
hypothesize, collect data, manipulate that data, and make conclusions. Too often, pre-
established science labs do not address all of these matters. The lichen study
encourages students to conduct investigations, use various higher-level thinking
skills, improve active participation in group work, and apply conclusions to work
towards improvements in their community. Additionally, it may be beneficial to
spend more time examining plant growth before beginning the lichen study.
Understanding the classification of trees based on their bark will most certainly help
students collect usable data.
Ultimately, using lichens as bioindicators is a powerful classroom activity that
employs a cost-effective means for measuring local air quality, while simultaneously
teaching aspects of plant biology, air chemistry, weather, and science process.
Gregory L. Smith is a teacher at Wheatridge Middle School in Gardner, Kansas.
Thomas R. Baker is project coordinator at the Center for Research on Learning
and the Center for Science Education at the University of Kansas in Lawrence.
Acknowledgement
The authors wish to acknowledge contributions to the study of lichens as
bioindicators for the classroom from Barbara Tinker of The Global Lab Project and
Dr. Steven B. Case of the PathFinder Science Network.
Resources
PathFinder Science Network—www.pathfinderscience.net
References
American Association for the Advancement of Science (AAAS). 1993. Benchmarks for
science literacy. New York, N.Y.: Oxford University Press Baker, T.R. and S.B. Case.
2000. Let GIS be your guide. The Science Teacher 67(8), 24–26.
Brodo, I.M., S.D Sharnoff, and S.S. Sharnoff. 2001. Lichens of North America. New
Haven, Conn.: Yale University Press.
Mitchell, A. 1999. The ESRI guide to GIS analysis: Geographic patterns and
relationships. Redlands, Ca.: ESRI Press.
National Research Council (NRC). 1996. National Science Education Standards.
Washington, D.C.: National Academy Press.
National Research Council (NRC). 1999. How people learn: Brain, mind, experience,
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