Get summay, questions, answers, solutions, notes, extras, PDF, competency-based questions of chapter- 3/unit I, Biodiversity and its Conservation: AHSEC Class 11 Environmental Education, which is part of the present syllabus. These solutions, however, should only be treated as references and can be modified/changed.
Summary
Biodiversity is the variety of all living things on Earth. This includes plants, animals, and tiny microorganisms. It also includes the genes they carry and the different environments they live in. Biodiversity is looked at on three levels: genetic, species, and ecosystem. Genetic diversity is the variety of genes within a single species. For example, different types of rice, like basmati and joha, exist because of genetic differences. These differences can create variations in size, color, or taste.
Species diversity refers to the number of different species on Earth. A species is a group of living things that can create fertile offspring. Horses and donkeys are different species, just as lions and tigers are. Ecosystem diversity is the variety of different habitats, like forests, deserts, and oceans. An ecosystem is a community where living things interact with each other and with non-living things like soil, air, and water.
Biodiversity is valuable to humans in many ways. It provides us with food, fuel, medicine, and clothing. About 90 percent of the world’s food comes from plants. Many medicines are also derived from nature, such as penicillin from a fungus and aspirin from a plant. This is called consumptive use. Productive use involves commercial products from nature, like silk from silkworms and wood for paper. Biodiversity also has social and cultural value. In India, many plants and animals are part of religious traditions. Some forests, called sacred groves, are protected because they are considered holy. There is also an ethical reason to protect biodiversity, as every species has a right to exist. The beauty of nature, or its aesthetic value, brings joy to people who visit parks and wild areas.
However, biodiversity is facing many threats. One major threat is habitat destruction, which happens when forests are cut down for farming, roads, or cities. Poaching, the illegal hunting of animals like rhinos and tigers for their horns or fur, is another serious problem. Overgrazing by livestock can damage grasslands and lead to soil loss. Climate change and global warming can harm species that cannot adapt to new conditions. Biopiracy, the act of taking natural resources or traditional knowledge from a place without permission to make money, is also a threat.
To protect biodiversity, conservation efforts are made. In-situ conservation means protecting species in their natural habitats, such as in national parks and wildlife sanctuaries. Kaziranga National Park in Assam is an example where rhinos are protected. Ex-situ conservation involves protecting species outside their natural homes, in places like zoos and botanical gardens. Countries also create laws to protect their natural wealth. India has several laws, like the Wildlife Protection Act, to prevent hunting and protect forests.
Textual/Exercise
1. Define the term biodiversity.
Answer: The term ‘biological diversity’ commonly shortened to biodiversity refers to the number, variety, and variability of all life forms on earth. These include millions of plants, animals and micro-organisms, the genes they contain, and the intricate ecosystems of which they are a part. Biodiversity is usually described at three levels: genetic, species and ecosystem diversity.
2. Explain with suitable examples – genetic diversity, species diversity and ecosystem diversity.
Answer: Genetic diversity is the diversity of genes within a species, which are passed down the generations. This type of diversity gives rise to the varieties of species. For example, basmati rice is distinct from joha rice. Some variations are easy to see, such as, size or colour.
Species diversity is explained by the fact that species is the unit used to classify the millions of life forms on earth. Each species is distinct from every other species. For example, horses and donkeys are distinct species, as are lions and tigers. What unites members of a species is that they are genetically so similar that they can produce fertile offspring.
Ecosystem diversity is the diversity of habitats which include the different life forms within itself. An ecosystem is a set of life forms like plants, animals, and micro-organisms interacting with one another and with non-living elements like soil, air, water, and minerals.
3. What are value of biodiversity?
Answer: The value of biodiversity is that it touches almost every aspect of our life. This diversity meets the food, medicinal, clothing, shelter, spiritual as well as the recreational needs of millions of people around the world. It also ensures that ecological functions such as the supply of clean water, nutrient cycling and soil protection are maintained. The values of biodiversity can be categorized as:
- Consumptive use
- Productive use
- Social use
- Ethical use
- Aesthetic use
4. What is consumptive value?
Answer: Consumptive value relates to biodiversity products like fuel, food, drugs, and fibres that have been used by man from time immemorial. About 90 per cent of the world’s food comes from plant species. About 80 per cent of the people in developing countries depend for primary healthcare on traditional medicine, most of which is derived from plants, and some from animal and mineral sources. Fuel wood, fossil fuels like coal and petroleum, natural gas, and minerals have been used by all of us.
5. What is productive value?
Answer: Productive value refers to the commercial products manufactured or prepared from the different resources of biodiversity. Many industries depend largely on plant materials, for example, the paper and pulp industry, sugar industry, plywood industry, and railway sleeper industry. Products obtained from animal diversity include the tusks of elephants, silk from silk worms, wool from sheep, and lac from lac insects.
6. What are major threats to biodiversity?
Answer: The major threats to biodiversity are:
a) Habitat destruction
b) Overgrazing
c) Poaching
d) Natural calamities
e) Climate change and global warming
f) Biopiracy
7. What are Ex-situ and In-situ conservation of biodiversity? Give examples of each.
Answer: In-situ conservation is the conservation of wild species of flora and fauna in their natural habitat, which means on-site preservation. Examples include biosphere reserves, national parks, wildlife sanctuaries, and reserve forests.
Ex-situ conservation is the conservation of plants and animals away from their natural habitat. This could be in zoological parks and botanical gardens or through forestry institutions and agricultural research centres.
8. What is biopiracy?
Answer: Biopiracy is a kind of procurement of biological resources from a country or a place and the subsequent patentisation of their products. Agents of some companies or other middle persons collect knowledge and valuable living materials from indigenous people and then proceed for patentisation on their own. Through such unethical means, they acquire the rights to market these products.
9. Mention two conservation strategies in our country.
Answer: Two conservation strategies in our country are:
- Environment Protection Act, 1986: This act relates to general measures to protect the environment, such as restriction on industrial and other processes or activities in specified areas.
- Forest (Conservation) Act, 1980: This act primarily focuses on prohibiting or regulating non-forest use of forest lands.
10. In which year the Earth Summit was held?
Answer: The Earth Summit was held in 1992 in Rio de Janeiro.
Extra/additional questions and answers
1. Describe in detail the three levels of biodiversity.
Answer: Biodiversity is usually described at three levels: genetic, species, and ecosystem diversity.
Genetic biodiversity is the diversity of genes within a species, which are passed down through generations. This type of diversity is what gives rise to the different varieties of a species. For instance, basmati rice is distinct from joha rice. Some of these genetic variations are easy to see, such as differences in size or colour, while other variations like taste or flavor can be perceived by other senses.
Species biodiversity refers to the variety of different species on earth. A species is the basic unit used to classify the millions of life forms. Each species is distinct from every other species; for example, horses and donkeys are distinct species, just as lions and tigers are. Members of the same species are united by the fact that they are genetically similar enough to produce fertile offspring. Species diversity is typically measured by the total number of species found within a specific, defined area.
Ecosystem biodiversity is the diversity of habitats that contain different life forms. An ecosystem is a community of life forms like plants, animals, and micro-organisms that interact with one another and with non-living elements such as soil, air, and water. Therefore, ecosystem diversity refers to the variety of these habitats and the different life forms within them. The term can also be used to describe the variety of ecosystems found within a larger biogeographical or political boundary.
48. Write short note on Ex-situ Conservation.
Answer: Ex-situ conservation is the conservation of plants and animals away from their natural habitat. This can be in zoological parks and botanical gardens or through forestry institutions and agricultural research centres. A lot of effort is underway to collect and preserve the genetic material of crops, animals, birds, and fish species. This work is being done by institutions such as the National Bureau of Plant Genetic Resources, New Delhi, and the National Bureau of Animal Genetic Resources, Karnal.
Extra/additional Fill in the Blanks
1. Biodiversity is usually described at ______ levels: genetic, species and ecosystem.
Answer: three
27. The Wildlife (Protection) Act was first enacted in ______.
Answer: 1972
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