GSEB Class 12 Biology Solutions Chapter 15 Biodiversity and Conservation

GSEB Class 12 Biology Biodiversity And Conservation Text Book Questions And Answers

Question 1. Name the three important components of biodiversity.
Answer: Biodiversity consists of three crucial elements:
1. Genetic diversity
2. Species diversity
3. Ecological diversity
In simple words: Biodiversity is divided into genetic, species, and ecosystem levels, each representing unique biological variety.

🎯 Exam Tip: When asked about components, clearly list and briefly define each type of diversity for full marks.

Question 2. How do ecologists estimate the total number of species present in the world?
Answer: Ecologists utilize a statistical approach to estimate the global species count. While the IUCN (International Union for Conservation of Nature) estimates over 1.5 million animal and plant species exist, many more remain undiscovered, particularly in tropical regions. Biologists frequently compare species richness between temperate and tropical areas, often focusing on well-studied groups like insects. By calculating the ratio of species richness in these regions, they project estimates for other plant and animal groups, leading to a comprehensive global total. Robert May, for instance, suggested that Earth's total global species biodiversity is approximately 7 million.
In simple words: Ecologists estimate global species by comparing known species in temperate and tropical zones, especially for well-studied groups, and then extrapolating these ratios to unknown groups, with estimates like Robert May's suggesting 7 million species.

🎯 Exam Tip: Mentioning both the IUCN estimate and Robert May's 7 million figure demonstrates a comprehensive understanding of estimation methods.

Question 3. Give three hypotheses for explaining why tropics show the greatest levels of species richness.
Answer: Tropical regions exhibit the highest levels of species richness due to several factors:
- **Absence of Major Catastrophes:** Unlike temperate zones, which have experienced extensive destruction from glaciations and other large-scale events, tropical areas have largely remained free from such widespread catastrophes.
- **Stable Environment:** Tropical climates are characterized by consistent, non-seasonal conditions, which foster greater species diversity and richness.
- **Abundant Solar Energy:** The tropics receive ample sunlight, directly contributing to high primary productivity and supporting a wider array of life.
In simple words: Tropics have high species richness due to their long-term climatic stability, consistent non-seasonal environment, and abundant solar energy supporting high productivity.

🎯 Exam Tip: Clearly listing and briefly explaining each hypothesis will help in scoring well, focusing on stability, solar energy, and lack of historical disturbances.

Question 4. What is the significance of the slope of regression in a species-area relationship?
Answer: The renowned German naturalist and geographer, Alexander von Humboldt, observed that species richness tends to rise with an increase in the explored area. This relationship, for diverse taxa, often takes the form of a rectangular hyperbola. It can be mathematically represented by the equation:
\( \log S = \log C + Z \log A \)
Where:
S = Species richness
A = Area
Z = Slope of the regression line (also known as the regression coefficient)
C = Y-intercept
Ecologists have found that the 'Z' value typically ranges from 0.1 to 0.2, showing remarkable consistency across different taxonomic groups or regions. However, for considerably larger areas, the slope of the regression line becomes much steeper, with 'Z' values ranging from 0.6 to 1.2.
In simple words: The slope of the regression line (Z) in the species-area relationship indicates how rapidly species richness increases with area; a higher Z value implies a steeper increase, especially in very large regions.

🎯 Exam Tip: Clearly state the equation, define its components, and explain how the Z-value varies for small versus large areas to demonstrate a complete understanding.

The Importance Of Species Diversity To The Ecosystem:

Ecologists propose that communities with greater species variety are typically more stable than those with less diverse communities. A stable community exhibits minimal yearly fluctuations in productivity, strong resistance to occasional natural or human-made disturbances, and resilience against invasion by non-native species. David Tilman, a renowned ecologist, demonstrated through extensive outdoor plot experiments that increased diversity directly correlates with enhanced productivity. This rich biodiversity and elevated productivity are crucial not only for maintaining a healthy ecosystem but also for ensuring human survival. As species loss accelerates, a pertinent question arises: Does the extinction of a few species truly impact us? For example, would the Western Ghats ecosystem lose functionality if a single tree frog species were to disappear? The exact consequences are often hard to ascertain. However, Stanford ecologist Paul Ehrlich’s "rivet popper hypothesis" offers valuable insight. It likens an ecosystem to an airplane, where thousands of rivets represent individual species holding all parts together. If passengers begin removing rivets to take home, the plane might initially function normally. Yet, as more and more rivets are removed, the structural integrity of the airplane (ecosystem) weakens progressively over time, ultimately leading to significant functional loss.

ℹ️ चित्र व्याख्या (Diagram Explanation): यह आरेख प्रजाति-क्षेत्र संबंध को दर्शाता है। इसमें दिखाया गया है कि प्रजाति समृद्धि (Species richness) अन्वेषित क्षेत्र (Area) के साथ कैसे बढ़ती है। लॉग-लॉग स्केल पर इस संबंध को एक सीधी रेखा के रूप में चित्रित किया गया है, जो बताता है कि क्षेत्र बढ़ने के साथ प्रजातियों की संख्या में वृद्धि एक पूर्वानुमेय पैटर्न का पालन करती है।

Question 5. What are the major causes of species losses in a geographical region?
Answer: The primary drivers of species loss in any geographical area include habitat destruction, hunting, habitat fragmentation, forest fires, introduction of alien species, co-extinction events, pollution, various disturbances, intensive agricultural practices, and the collection of species for pharmaceuticals, cosmetics, perfumes, and aphrodisiacs.
(i) **Habitat Loss and Fragmentation:** This stands as the leading cause of biodiversity depletion, resulting from activities such as deforestation, conversion of grasslands to agriculture, wetland reclamation, and forest burning. A prime example is the tropical rainforest, which once covered 1.4% of Earth’s land and now covers only 6%. The Amazon rainforest, vital for global oxygen production, is being cleared for soybean cultivation and cattle ranching. The fragmentation of forests into smaller, isolated patches due to human development also contributes significantly to species disappearance.
(ii) **Overexploitation:** While biodiversity fulfills essential human needs, excessive demands transform into greed, leading to the unsustainable exploitation of natural resources. Historical instances like the extinction of Steller's sea cow and the passenger pigeon underscore the devastating impact of human overexploitation.
(iii) **Alien Species Invasions:** The introduction of non-native, or exotic, species into new geographical areas by humans can severely harm indigenous species, often leading to their extinction. A notable case is the Nile perch, whose introduction into Lake Victoria in East Africa caused the extinction of approximately 200 species of native cichlid fish. Invasive plants like carrot grass (*Parthenium*), Lantana, and water hyacinth (*Eichhornia*) have similarly degraded environments. The African catfish, *Clarias gariepinus*, introduced for aquaculture, now endangers native catfish species. Furthermore, the American cockroach, *Periplaneta americana*, introduced to India via food shipments, has largely displaced the native *Blatta orientalis*.
(iv) **Co-extinctions:** This phenomenon occurs when the extinction of one species triggers the extinction of another species that is dependent on it. For example, if a host fish species becomes extinct, its associated parasite species will also face extinction.
In simple words: Major causes of species loss are habitat destruction, overexploitation, alien species invasions, and co-extinctions, all contributing to a rapid decline in global biodiversity.

🎯 Exam Tip: When discussing species loss, ensure you explain each major cause with a relevant example to illustrate its impact effectively.

Question 6. How is biodiversity important for ecosystem functioning?
Answer: Biodiversity is fundamentally important for the healthy functioning of ecosystems, based on several arguments:
(i) **Narrowly Utilitarian Perspective:** This perspective highlights the direct economic benefits humanity gains from biodiversity. These include essential resources like food, firewood, fibers, construction materials, and numerous industrial products such as tannins, dyes, lubricants, resins, and perfumes. Additionally, over 25% of modern medicines originate from plants, with nearly 25,000 plant species contributing to traditional medicinal practices globally. The potential for discovering new medicinal plants, especially in tropical rainforests, remains vast.
(ii) **Broadly Utilitarian Perspective:** This view emphasizes biodiversity's crucial role in providing diverse ecosystem services. For example, the Amazon rainforest alone generates 20% of Earth's atmospheric oxygen through photosynthesis, demonstrating an invaluable natural service. Other indirect benefits include:
    a. **Pollination:** Essential for plant reproduction, pollination, carried out by agents like bees, birds, and bats, is vital for fruit and seed production.
    b. **Aesthetic and Cultural Benefits:** Biodiversity offers significant aesthetic and cultural value, supporting activities like ecotourism, bird watching, wildlife photography, pet-keeping, and gardening. Plants such as Tulsi (*Ocimum sanctum*) and Pipal (*Ficus religiosa*) hold sacred importance in many Indian traditions. Recognizing plants and animals as symbols of national heritage, experiences like forest walks, observing blooming spring flowers, or listening to a bulbul’s song provide immense pleasure and serenity.
(iii) **Ethical Argument:** This perspective asserts that humanity has a moral obligation to protect Earth's biodiversity, encompassing millions of plants, animals, and microbes with whom we share our planet. It underscores the philosophical and spiritual understanding that every species possesses its own inherent value and right to exist.
In simple words: Biodiversity is crucial for ecosystems due to direct economic benefits (food, medicine), essential ecosystem services (oxygen, pollination), and intrinsic ethical responsibilities to protect all life forms.

🎯 Exam Tip: Structure your answer by clearly distinguishing between the utilitarian (narrow and broad) and ethical arguments for biodiversity's importance, providing specific examples for each.

Question 7. What are sacred groves? What is their role in conservation?
Answer: Sacred groves are designated areas, revered by local communities for religious reasons, where any form of exploitation or destruction of nature is strictly prohibited. Examples include the Kumaon regions, Khasi Hills in Meghalaya, Aravalli hills in Rajasthan, and the Western Ghats across Kerala and Karnataka. These groves serve as vital refuges for numerous rare and threatened plant and animal species, preserving them from exploitation and contributing significantly to biodiversity conservation.
In simple words: Sacred groves are forest patches protected by religious and cultural beliefs, acting as natural sanctuaries that safeguard rare and threatened species from human exploitation.

🎯 Exam Tip: Define sacred groves by their religious significance and highlight their function as protective refuges for endangered biodiversity, mentioning specific examples for context.

Question 8. Among the ecosystem services are control of floods and soil erosion. How is this achieved by the biotic components of the ecosystem?
Answer: Ecosystems inherently manage floods and soil erosion through various natural processes, often enhanced by sustainable human practices. Flood control involves extensive reforestation efforts and the development of structures like levees, dams, reservoirs, and floodways. To combat soil erosion, methods such as mulching (covering bare soil with organic materials like straw, grasses, or husks), cultivating cover crops and green manures, implementing mixed cropping, timely planting at the onset of the rainy season, leaving crop residues post-harvest, practicing agroforestry (integrating trees with agricultural crops), and minimizing soil disturbance through reduced cultivation are all effective strategies.
In simple words: Ecosystems control floods and soil erosion through biotic elements like dense vegetation and roots that stabilize soil, absorb water, and slow down runoff, naturally preventing damage.

🎯 Exam Tip: Focus on how vegetation (trees, cover crops, roots) directly contributes to flood mitigation and soil stabilization, linking these biotic components to ecosystem services.

Question 9. The species diversity of plants (22 percent) is much less than that of animals (72 percent). What could be the explanations for how animals achieved greater diversification?
Answer: The significant disparity in species diversity, with animals (72%) far exceeding plants (22%), can be attributed to key biological differences:
- **Plant Characteristics:** Plants are sessile organisms, requiring fewer complex adaptations to acquire essential raw materials and sunlight. This often results in reduced competition for resources within their immediate environment, leading to less pressure for extensive diversification.
- **Animal Characteristics:** In contrast, animals are mobile and frequently gather in specific areas of vegetation. This mobility and congregation intensify competition for resources, mates, and territory, driving strong selective pressures that foster rapid species variation and, consequently, greater overall diversity.
In simple words: Animals diversified more than plants because their mobility and heightened competition for resources drive more rapid adaptation and speciation compared to sessile plants, which face less pressure for complex adaptations.

🎯 Exam Tip: Contrast the mobility and competition dynamics of animals with the sessile nature and simpler resource acquisition of plants to explain the difference in diversification levels.

Question 10. Can you think of a situation where we deliberately want to make a species extinct? How
Answer: If a particular species faces extinction due to any specific activity, it invariably impacts the survival of other interconnected plant and animal species. A classic example illustrating this interdependent relationship is that between the Calvaria tree and the now-extinct Dodo bird.
In simple words: Deliberately causing extinction is generally avoided due to the interconnectedness of ecosystems, where the loss of one species can trigger cascading negative effects on others, as seen with the Dodo and Calvaria tree.

🎯 Exam Tip: While the question asks for deliberate extinction, the provided answer focuses on the *consequences* of extinction. Emphasize ecological interdependence and the Dodo-Calvaria example, as given in the source text.

GSEB Class 12 Biology Biodiversity And Conservation Additional Important Questions And Answers

Question 1. Complete the following, the name of scientists and their area in biodiversity conservation is given.
a. ........(a).. : Biodiversity
b. Robert May : ........(b).........
c. .(c). : Species richness
d. Paul Ehrlich : ........(d).........
Answer: Here are the completed details regarding scientists and their contributions to biodiversity conservation:
(a) Edward Wilson: Biodiversity
(b) Robert May: Global species diversity
(c) Alexander von Humboldt: Species richness
(d) Paul Ehrlich: Rivet popper hypothesis
In simple words: This question lists key scientists and their primary contributions to understanding and conserving biodiversity, such as Edward Wilson for biodiversity concept and Paul Ehrlich for the rivet popper hypothesis.

🎯 Exam Tip: Memorizing the key scientists and their associated concepts or contributions is essential for quick recall in fill-in-the-blank or matching questions.

Question 2. A graph on species richness is given below. Complete the equations (a) and (b) according to Alexander von Humboldt.
a. Log S = log C + Z log A
b. S = CAZ
S - Species richness, A – Area, Z – Slope of the line (regression coefficient), C = Y-intercept
Answer: To complete the equations related to species richness, based on Alexander von Humboldt's work:
(a) \( \log S = \log C + Z \log A \)
(b) \( S = CA^Z \)
Where:
S represents Species richness
A denotes Area
Z is the Slope of the line (or regression coefficient)
C is the Y-intercept
In simple words: The species-area relationship, following Humboldt, can be expressed linearly on a log-log scale as \( \log S = \log C + Z \log A \), or as a power function \( S = CA^Z \), linking species richness (S) to area (A).

🎯 Exam Tip: Understand both the logarithmic and exponential forms of the species-area relationship and the meaning of each variable (S, A, Z, C).

Question 3. The table shows the number of species of birds seen in some places.
Colombia – 1400
New York - 105
Greenland - 56
India - 1200
South America (Amazon) – 1300
What could be the reason for the difference in the number of bird species present? Justify your answer.
Answer: The variation in bird species observed across different locations is primarily due to latitudinal gradients. Species diversity generally diminishes as one moves from the equator towards the polar regions. The latitudinal band between 23.5°N and 23.5°S (the tropics) typically hosts a greater number of species compared to temperate or polar zones. As demonstrated in the provided table, Colombia, India, and the Amazon basin fall within the tropical belt, exhibiting higher bird species counts. Conversely, New York (41°N) and Greenland (71°N) are located at higher latitudes, which correlates with a reduction in species numbers. This pattern is largely attributable to the increased availability of solar energy in tropical regions, fostering greater productivity and supporting diverse life forms.
In simple words: Bird species diversity is highest near the equator (tropics) and decreases towards the poles, primarily because tropical regions receive more solar energy, leading to higher productivity and more stable environments.

🎯 Exam Tip: Link the observed differences in species numbers directly to latitudinal position, explaining the role of solar energy and stable climates in tropical biodiversity.

Question 4. In India, we have our own species of cockroach Blatta orientalis. But now we can see only American species Periplaneta americana.
a. What is the reason for this condition?
b. Give another example for the same condition.
c. Mention other causes for biodiversity losses.
Answer: The shift from native Indian cockroaches, *Blatta orientalis*, to predominantly American species, *Periplaneta americana*, can be explained as follows:
(a) This situation arises from the introduction of exotic (alien) species.
(b) Another instance of this phenomenon is the introduction of the Nile perch into Lake Victoria in East Africa, which resulted in the extinction of approximately 200 species of native cichlid fish.
(c) Other significant factors contributing to biodiversity loss include:
- Habitat loss and fragmentation
- Overexploitation of natural resources
- Co-extinctions, where the disappearance of one species leads to the extinction of another dependent species.
In simple words: The replacement of native species by foreign ones is due to alien species introduction, as exemplified by the Nile perch in Lake Victoria; other biodiversity losses stem from habitat destruction, overexploitation, and co-extinctions.

🎯 Exam Tip: Focus on 'alien species invasion' as the core reason for native species displacement and provide diverse examples for other causes of biodiversity loss.

Question 5. Amazon rain forest has the greatest biodiversity on earth. List any two hypotheses that account for the greater biological diversity.
Answer: The Amazon rainforest, a tropical region, exhibits unparalleled biodiversity, which can be attributed to several contributing factors:
- **Absence of Catastrophic Events:** Tropical zones have largely been spared from major catastrophic events, such as glaciations and other large-scale destructive forces that have historically impacted temperate regions. This long-term environmental stability fosters species accumulation.
- **Non-Seasonal Environment:** Tropical climates experience remarkably consistent, non-seasonal climatic conditions. This environmental uniformity promotes consistent resource availability and reduces stress, thereby enhancing species richness and diversity.
- **Abundant Solar Energy:** Receiving high levels of solar radiation, tropical ecosystems benefit from exceptional primary productivity. This abundant energy flow supports a vast and diverse biological community.
In simple words: The Amazon's high biodiversity is linked to its long-term environmental stability, consistent non-seasonal climate, and abundant solar energy, which together facilitate continuous evolution and species accumulation.

🎯 Exam Tip: When discussing high biodiversity in the Amazon, emphasize long evolutionary time, stable climate, and high solar energy as key contributing hypotheses.

Question 6. Recently a country held its cabinet meeting under the sea.
a. Name the country.
b. Why was it done?
Answer: Regarding the recent underwater cabinet meeting:
(a) The country that conducted its cabinet meeting underwater was the Maldives, located in the Indian Ocean.
(b) This unprecedented action was undertaken to draw global attention to the critical issues of global warming and the alarming rise in ocean water levels.
In simple words: The Maldives held an underwater cabinet meeting to highlight the urgent threats of global warming and rising sea levels impacting their island nation.

🎯 Exam Tip: Remember the Maldives and their symbolic action to raise awareness about climate change and its direct impact on low-lying island nations.

Question 7. What's species diversity?
Answer: Species diversity refers to the total array of different species found inhabiting a particular geographical area or ecosystem.
In simple words: Species diversity is the variety of different species living in a specific region.

🎯 Exam Tip: A precise, concise definition of species diversity is key, focusing on the variety of species within a given area.

Question 8. Suppose you are the Secretary of your school Science Club and you are invited by the local body member to give a talk on “biodiversity” for the literacy mission. Prepare a note to be presented.
Hints: Importance of wildlife, conservation, damages.
Answer: Good morning everyone. Today, I want to discuss the profound significance of biodiversity, particularly wildlife, for our planet and humanity. Wildlife, as defined by naturalists, encompasses all non-cultivated plants, non-domesticated animals, and microorganisms. It represents the living organisms that are neither human nor domesticated, including mammals, birds, and fish. The importance of wildlife to humankind is multifaceted:
- **Ecological Value:** The loss of wildlife can severely disrupt natural ecological balances, leading to cascading environmental consequences.
- **Commercial Value:** Many wildlife products, such as furs, elephant ivory, rhinoceros horns, and musk deer glands, possess significant international market value.
- **Game Value:** Wildlife also holds considerable recreational and sporting value.
- **Scientific Value:** Wild species serve as crucial genetic reservoirs, providing a gene pool vital for breeding programs in agriculture, animal husbandry, and fisheries.
- **Aesthetic Value:** The inherent beauty and appeal of wildlife offer immense aesthetic pleasure and enrich human lives.
- **Medicinal Value:** A vast array of drugs, essential for treating human ailments, are derived from wild plants and animals.
In simple words: Wildlife, encompassing all non-domesticated life, is vital for ecological balance, provides commercial and scientific resources, offers aesthetic value, and serves as a source for medicines, underscoring its immense importance.

🎯 Exam Tip: When preparing a talk, structure your points clearly, starting with a definition and then detailing different types of value (ecological, commercial, scientific, aesthetic, medicinal) with brief explanations.

Question 9. What are National Parks? Explain any five National Parks found in India.
Answer: National Parks are rigorously protected areas specifically established for the enhancement and preservation of wildlife, where activities like forestry, grazing, or cultivation are strictly prohibited.
Here are five notable National Parks in India:
1. **Shivpuri National Park:** Situated near Gwalior in Madhya Pradesh, this park is renowned for its populations of tigers, cheetahs, and sambhar deer.
2. **Guindy National Park:** Located near Chennai (formerly Madras) in Tamil Nadu, it is home to albino deer, blackbuck, cheetahs, and a notable snake park.
3. **Betla National Park:** Found in Palamu, Bihar, this park provides habitat for elephants and tigers.
4. **Dachigam National Park:** Located in Srinagar, Jammu and Kashmir, this park protects wildlife including leopards, black bears, brown bears, musk deer, hangul (Kashmir stag), and various scrow species.
5. **Bandhavgarh National Park:** Situated in Shahdol, Madhya Pradesh, this park is famous for its white tigers, panthers, cheetahs, bison, nilgai, barking deer, and wild boar.
In simple words: National Parks are highly protected areas for wildlife where human activities are restricted. India has many, like Shivpuri (tigers), Guindy (deer), Betla (elephants), Dachigam (leopards), and Bandhavgarh (white tigers).

🎯 Exam Tip: Provide a clear definition of National Parks and then list five examples, each with its location and key protected animal species for maximum clarity.

Question 10. The graph shown below indicates the per head consumption of energy. If it is going on in way to face this situation.

ℹ️ चित्र व्याख्या (Diagram Explanation): यह ग्राफ 'प्रति व्यक्ति ऊर्जा खपत' को 'समय' के साथ दर्शाता है। इसमें दिखाया गया है कि कैसे समय के साथ ऊर्जा की प्रति व्यक्ति खपत बढ़ती जा रही है, जो एक अस्थिर या बढ़ती प्रवृत्ति को इंगित करती है जिसके लिए वैकल्पिक समाधानों की आवश्यकता है।
Answer: Considering the trend of per capita energy consumption, alternative strategies are crucial to manage future energy demands:
- **Reduce Fossil Fuel Reliance:** Implement policies and technologies to limit the use of non-renewable fossil fuels.
- **Promote Efficient Stoves:** Encourage the adoption of smokeless and highly efficient wood stoves to minimize fuel consumption and pollution.
- **Harness Solar Energy:** Invest in and utilize solar energy as a sustainable and renewable power source.
- **Utilize Biogas Plants:** Expand the use of biogas plants for energy generation from organic waste.
- **Develop Hydroelectric, Wind, and Tidal Power:** Explore and develop hydroelectric projects, wind farms, and tidal energy systems to diversify and increase renewable energy production.
- **Cultivate Fuelwood Trees:** Undertake initiatives for growing fuelwood trees and shrubs to ensure a sustainable supply of biomass energy.
In simple words: To manage rising energy consumption, we must reduce fossil fuel use, adopt efficient technologies, and promote renewable sources like solar, biogas, hydro, wind, tidal power, and sustainable fuelwood cultivation.

🎯 Exam Tip: Focus on a balanced approach that includes both reducing consumption and promoting diverse renewable energy sources to address the energy crisis effectively.

Question 11. The Periyar Wildlife Sanctuary is the pride of Kerala.
1. Where is this sanctuary located in Kerala?
2. Give the importance of this place.
Answer: Regarding the Periyar Wildlife Sanctuary, a significant natural heritage of Kerala:
1. The sanctuary is situated in Thekkady, within the Idukki district of Kerala.
2. Its primary importance lies in providing crucial protection to iconic animal species, including tigers and elephants.
In simple words: Periyar Wildlife Sanctuary is in Thekkady, Idukki district, Kerala, and is crucial for protecting tigers and elephants.

🎯 Exam Tip: Remember the location (Thekkady, Idukki) and the key protected species (tigers, elephants) for Periyar Wildlife Sanctuary.

Question 12. The following figure is of an eminent environmentalist.
a. Name the personality.
b. Mention his contribution in this regard.
c. To which state does he belong?

ℹ️ चित्र व्याख्या (Diagram Explanation): यह चित्र सुंदरलाल बहुगुणा को दर्शाता है, जो भारत के एक प्रसिद्ध पर्यावरणविद् और गांधीवादी कार्यकर्ता थे। वे विशेष रूप से चिपको आंदोलन में अपनी महत्वपूर्ण भूमिका और पर्यावरण संरक्षण के लिए अपने अथक प्रयासों के लिए जाने जाते हैं।
Answer: Concerning the eminent environmentalist shown:
(a) The personality is Sundarlal Bahuguna.
(b) His notable contribution was leading the 'Chipko Movement', and he famously articulated the slogan: 'Ecology is the permanent economy'.
(c) He hailed from the state of Uttarakhand.
In simple words: The environmentalist is Sundarlal Bahuguna from Uttarakhand, known for leading the Chipko Movement and coining the slogan "Ecology is the permanent economy."

🎯 Exam Tip: Connect Sundarlal Bahuguna directly to the Chipko Movement and his famous ecological slogan, remembering his origin in Uttarakhand.

Question 13. There is a type of conservation of genetic resources through their maintenance within the natural or man-made ecosystems.
a. Which type of conservation is this?
b. Give the importance of the protected areas and the divisions involved in this.
Answer: Regarding the conservation of genetic resources maintained within natural or human-modified ecosystems:
(a) This method is known as In-situ conservation.
(b) Protected areas are vital terrestrial or marine regions dedicated to safeguarding and sustaining biodiversity, along with natural resources. These areas are categorized into several divisions, including National Parks, Wildlife Sanctuaries, Biosphere Reserves, Cultural landscapes, and Natural Monuments.
In simple words: This refers to In-situ conservation, which protects genetic resources within their natural habitats. Protected areas like National Parks, Sanctuaries, and Biosphere Reserves are key divisions for preserving biodiversity.

🎯 Exam Tip: Distinguish In-situ conservation by its "on-site" nature and list the various types of protected areas as its practical implementation.

Question 14. Even though Kerala is a small state, she has two National Parks, three Wildlife Sanctuaries and two Biosphere Reserves.
a. Prepare a radio talk on 'the conservation of nature' giving emphasis to Kerala and the animals to be protected there.
Answer: Good morning listeners. Today, let's talk about 'Nature Conservation,' with a special focus on Kerala, a small state with a big commitment to biodiversity. Kerala boasts two National Parks, three Wildlife Sanctuaries, and two Biosphere Reserves, demonstrating a robust effort to protect its unique flora and fauna.
**National Parks** are strictly reserved areas dedicated to wildlife betterment, where human activities like forestry or cultivation are forbidden. They protect entire ecosystems.
**Wildlife Sanctuaries** are areas primarily dedicated to animal protection, permitting limited human activities like timber collection or minor forest products, provided they don't harm the wildlife.
**Biosphere Reserves** are large protected zones for both terrestrial and coastal ecosystems, aiming to conserve genetic resources and promote sustainable development.
In Kerala, these protected areas are crucial for safeguarding species like tigers, elephants, Nilgiri Tahr, and numerous endemic plants, ensuring their survival and the health of our natural heritage. Our collective efforts in conserving these habitats are vital for maintaining ecological balance and securing a sustainable future.
In simple words: A radio talk on nature conservation in Kerala would highlight its National Parks, Wildlife Sanctuaries, and Biosphere Reserves, emphasizing their role in protecting iconic species like tigers, elephants, and Nilgiri Tahr for ecological balance.

🎯 Exam Tip: When writing a talk, use a clear, engaging structure: introduction, definition of key terms (National Park, Sanctuary, Biosphere Reserve), specific examples from Kerala, and a concluding call to action on conservation.

Question 15. We heard of the slogans “we two have two” and “one family one tree”. Give the importance of these slogans according to your views.
Answer: The slogans 'We Two Have Two' and 'One Family, One Tree' carry significant importance for sustainable living and environmental conservation:
**'We Two Have Two':** This slogan advocates for responsible family planning. Historically, the combined population of India, Pakistan, and Sri Lanka was 53 crore in 1947; today, India alone accounts for 105 crore. Continued unchecked population growth will inevitably lead to severe shortages of essential resources like food, housing, and potable water. Adhering to policies promoting smaller families is crucial to avert future crises. The example of China's stringent 'one-child' policy (with penalties for second children) highlights proactive measures other nations have taken.
**'One Family, One Tree':** This slogan promotes afforestation and environmental stewardship. For instance, a target was set to plant at least 100 million trees by 2007, with the broader goal of fostering public awareness and participation in environmental efforts. Planting a vast number of trees annually is essential for ecological balance, combating climate change, and improving air quality.
In simple words: 'We Two Have Two' promotes population control to prevent resource scarcity, while 'One Family, One Tree' encourages tree planting for environmental sustainability and ecological balance.

🎯 Exam Tip: Clearly articulate the relevance of each slogan—'We Two Have Two' for population management and 'One Family, One Tree' for environmental restoration—using historical context and future implications.

Question 16. Select the correct statements from the following
• IUCN red list is a catalogue of animals facing risk of extinction
• 3rd October is observed as World Animal Day.
• Eravikulam National Park is in Karnataka.
• Morphine is extracted from Papaver somniferum.
Answer: Upon reviewing the statements, the correct ones are:
- The IUCN Red List serves as a comprehensive inventory of animal species that are at risk of extinction.
- October 3rd is recognized annually as World Animal Day.
- Morphine is derived from *Papaver somniferum* (the opium poppy).
In simple words: The correct statements identify the IUCN Red List as tracking endangered animals, October 3rd as World Animal Day, and *Papaver somniferum* as the source of morphine.

🎯 Exam Tip: For multiple-choice or true/false questions, identify factual inaccuracies. Here, knowing Eravikulam National Park is in Kerala, not Karnataka, is critical.

Question 17. Based on this picture given below, prepare a short note on Eravikulam National Park.

ℹ️ चित्र व्याख्या (Diagram Explanation): यह चित्र एक नीलगिरी तहर को दर्शाता है, जो पश्चिमी घाट में पाई जाने वाली एक लुप्तप्राय बकरी प्रजाति है। नीलगिरी तहर एराविकुलम राष्ट्रीय उद्यान का एक महत्वपूर्ण निवासी है, जिसके संरक्षण के लिए यह पार्क विशेष रूप से स्थापित किया गया था।
Answer: Eravikulam National Park, located in the Devikulam taluk of Idukki district, Kerala, was initially designated as a sanctuary in 1975 to safeguard the Nilgiri Tahr. Recognizing its significant ecological, faunal, floral, geomorphological, and zoological value, it was elevated to a National Park status in 1978. Spanning 97 square kilometers, the park features expansive rolling grasslands and high-altitude *shola* forests, offering landscapes comparable to alpine regions.
Beyond its iconic Nilgiri Tahr population, which stood at 1317 individuals according to the 1991 census (up from 885 in 1989), the park is also home to diverse wildlife. Tigers, panthers, and wild dogs are frequently observed in both grasslands and *shola* forests. Civet cats and jungle cats inhabit the *sholas*, while sloth bears, Nilgiri langurs, and wild boars are commonly found in the *sholas* and their peripheries. Notably, the park is also a habitat for the Atlas moth, recognized as the world's largest moth species.
In simple words: Eravikulam National Park in Kerala protects the Nilgiri Tahr and diverse wildlife like tigers and elephants across 97 sq.km of grasslands and *shola* forests, having been upgraded from a sanctuary in 1975 to a National Park in 1978.

🎯 Exam Tip: When describing a national park, include its location, primary purpose (e.g., protecting Nilgiri Tahr), key habitats (grasslands, shola forests), and other significant fauna for a complete answer.

Question 18. There is shift in the policy of animal collection in the zoo from 'unlimited animals and limited facilities' to 'limited animals and adequate facilities'. Give reason.
Answer: The operational philosophy of zoos has evolved significantly, shifting from an earlier model of collecting 'unlimited animals with limited facilities' to focusing on 'limited animals with adequate facilities.' This change is driven by a modern understanding of zoos as essential conservation and educational centers. Contemporary zoos prioritize captive breeding programs for rare and endangered species, while also engaging in scientific research to advance wildlife conservation and management. This strategic pivot ensures that zoos contribute meaningfully to species preservation and public education, moving beyond their historical role as mere entertainment venues.
In simple words: Zoos have shifted from large collections with poor facilities to fewer animals with better care because their role evolved to focus on conservation, captive breeding of endangered species, education, and scientific research.

🎯 Exam Tip: Highlight the transition of zoos from mere display centers to active conservation and research hubs, emphasizing captive breeding and public education as key reasons for the policy change.

Question 19. Suggest a proper title for a poster that you have prepared as a part of Wildlife Week Celebrations related with 'tiger conservation'.
Answer: A suitable title for such a poster would be 'The Tiger: Our National Pride - Let Them Live Freely.'
In simple words: This slogan highlights the tiger's importance and the need for its unhindered survival.

🎯 Exam Tip: Effective poster titles are concise, impactful, and clearly convey the conservation message to the audience.

Question 20. Who proposed the rivet popper hypothesis? Explain the same with reference to the ecosystem.
Answer: This hypothesis was put forward by Paul Ehrlich. It conceptualizes an ecosystem as an airplane, where each rivet represents a species. If passengers start removing rivets (species) one by one, the initial removals might not severely impact the plane's (ecosystem's) functioning. However, as more and more rivets are taken out, the plane becomes increasingly unstable and eventually crashes, signifying the ecosystem's collapse. The loss of critical rivets, such as those on the wings (keystone species), poses a far greater threat to flight safety (ecosystem stability) than the removal of non-essential ones (less critical species).
In simple words: The rivet popper hypothesis, by Paul Ehrlich, compares an ecosystem to an airplane with species as rivets; losing too many, especially vital ones, can cause the entire system to collapse.

🎯 Exam Tip: Understanding the analogy of the rivet popper hypothesis is crucial for explaining the interconnectedness and importance of each species within an ecosystem.

Question 21. The prosperity of human beings in the whole world lies in the prosperity of nature. Justify this statement.
Answer: Indeed, human well-being across the globe is intrinsically linked to the health of nature. The degradation of land resources, through issues like soil erosion, salinization, acidification, alkalinization, and waterlogging, along with human activities such as road and railway construction, dam building, urbanization, industrialization, and mining, profoundly alters ecosystems. These alterations negatively impact plants, which serve as the fundamental producers, providing food for all life. While plant resources are renewable, they are rapidly diminishing due to deforestation, overgrazing, forest fires, and environmental pollution. Preserving ecosystems is therefore essential for human prosperity.
In simple words: Human welfare depends entirely on a healthy environment because natural resource depletion and pollution directly harm the ecosystems that provide essential resources like food and clean air.

🎯 Exam Tip: When justifying statements like this, it's important to provide specific examples of human activities impacting nature and the resulting consequences for human life.

Question 22. The fragmentation of a forest and deforestation lead to the disappearance of species and drastic climatic variation.a. Give some adverse effects of indiscriminate cutting down of forests. b. Suggest some measures to check deforestation.
Answer:a. The indiscriminate felling of forests, known as deforestation, primarily results in severe soil erosion. Raindrops directly hit the exposed ground, dislodging soil particles that are then carried into rivers, leading to riverbed sedimentation. Forests also play a crucial role in regulating climate. b. Deforestation can be curbed through a combination of public awareness campaigns and stringent legislative actions.
In simple words: Deforestation causes soil erosion and affects climate, so public education and strict laws are needed to stop it.

🎯 Exam Tip: When discussing environmental issues, always include both the ecological consequences and potential solutions, emphasizing human responsibility.

Question 23. Give differences between National Park, Sanctuary and Biosphere Reserves.
Answer:Biosphere Reserves: These are designated land or coastal areas aimed at conserving entire ecosystems and their genetic resources. The concept was initiated by UNESCO in 1975 under its Man and Biosphere Programme. India currently has 14 Biosphere Reserves. National Parks: These are strictly reserved areas for wildlife welfare, where activities such as cultivation, grazing, and private ownership rights are strictly prohibited. Habitat manipulation is also not allowed. India has 90 National Parks. Wildlife Sanctuaries: These areas are dedicated to protecting specific animal species. Activities like timber collection, minor forest product gathering, and private ownership rights are permitted, provided they do not negatively impact the welfare of the animals. India boasts 448 wildlife sanctuaries.
In simple words: Biosphere reserves protect entire ecosystems, national parks strictly prohibit human activities for wildlife, and sanctuaries focus on animal protection while allowing limited human activities.

🎯 Exam Tip: Differentiating between these protected areas requires understanding their primary conservation goals and the extent of human activity permitted within each.

Question 24. In 1992 the Earth Summit was held at Rio de Janeiro to conserve biodiversity. Give the objectives attained by that Summit.
Answer: The 1992 Earth Summit, held in Rio de Janeiro, achieved several key objectives concerning biodiversity conservation:
- Conservation of biological diversity.
- Equitable sharing of benefits derived from the utilization of genetic resources.
In simple words: The Rio Earth Summit in 1992 aimed to conserve biodiversity and ensure fair sharing of benefits from genetic resources.

🎯 Exam Tip: Key international summits like the Earth Summit are important for understanding global environmental policy; remember their primary objectives.

Question 25. Mention the different wildlife organisations.
Answer: Several organizations are dedicated to wildlife conservation:
The Nature Conservancy: This organization partners with local communities, businesses, and individuals globally to protect vast tracts of land (over 100 million acres). Its objective is to preserve entire wildlife communities and their diverse species, adopting a holistic approach crucial for planetary health.
The World Wildlife Fund (WWF): WWF collaborates with multilateral and bilateral agencies to promote sustainable development in developing countries. Its three main goals are to safeguard natural ecosystems and wild populations, minimize pollution, and encourage efficient, sustainable use of natural resources.
The Natural Resources Defense Council (NRDC): An environmental advocacy group comprising over 300 lawyers, scientists, and other professionals, NRDC boasts approximately 1.3 million members worldwide.
The Sierra Club: Established in 1892 by naturalist John Muir, this grassroots organization strives to protect ecological communities, advocate for smart energy solutions, and preserve America's wilderness areas for future generations.
In simple words: Major wildlife organizations like The Nature Conservancy, WWF, NRDC, and The Sierra Club work to protect ecosystems, wild animals, reduce pollution, and promote sustainable practices globally.

🎯 Exam Tip: When listing organizations, briefly describe their mission or key activities to demonstrate a clear understanding of their role in conservation.

Question 26. Silent Valley is a National Reserve Forest in Kerala. Why is it called so?
Answer: Silent Valley is known as a National Reserve Forest in Kerala because of its remarkably undisturbed ecosystem. The name "Silent Valley" is derived from the absence of noisy cicadas, typically found in tropical forests, which indicates a pristine and largely untouched natural environment.
In simple words: Silent Valley is a National Reserve Forest in Kerala, named for the unusual quietness due to the absence of cicadas, signifying its untouched natural state.

🎯 Exam Tip: Specific details like the reason for a name (e.g., absence of cicadas) can be important for demonstrating in-depth knowledge about a particular conservation area.

Question 27. Write an explanatory note on the efforts for the conservation of biodiversity in India.
Answer: Efforts to conserve biodiversity in India primarily fall into two categories: in-situ and ex-situ conservation.
I. In-situ Conservation: This approach involves maintaining genetic resources within their natural or human-managed ecosystems. It includes safeguarding typical ecosystems through a network of protected areas such as National Parks, Sanctuaries, Biosphere Reserves, cultural landscapes, natural monuments, hot spots, and sacred groves.
Hot Spots: Conservationists have identified specific regions characterized by extremely high species richness and a significant degree of endemism (species found exclusively in that region). These hot spots are the richest yet most threatened reservoirs of plant and animal life globally. The concept, introduced by Norman Myers in 1988, initially designated 25 biodiversity hot spots, with nine more added later, bringing the total to 34 worldwide. Three of these hot spots-the Western Ghats and Sri Lanka, Indo-Burma, and the Himalayas-are found in India's high biodiversity regions. Despite covering less than 2% of Earth's land area, hot spots harbor an exceptionally high number of species and play a crucial role in reducing mass extinction by nearly 30%.
Biosphere Reserves: These protected land or coastal areas are established to conserve ecosystems and genetic resources. India has 14 Biosphere Reserves, conceptualized by UNESCO in 1975 under its Man and Biosphere Programme.
National Parks: These areas are strictly reserved for wildlife welfare, prohibiting activities like cultivation, grazing, and private ownership. India has 90 National Parks.
Wildlife Sanctuaries: These areas focus on animal protection. Timber collection, minor forest product gathering, and private ownership are allowed if they don't disturb animal well-being. India has 448 wildlife sanctuaries.
Sacred Groves: These are forest patches protected by tribal communities and religious groups due to their spiritual significance. In Kerala, they are called sacred groves and serve as refuges for threatened species, notably found in Khasi and Jaintia Hills, Aravalli hills, Western Ghats, and parts of Madhya Pradesh.
II. Ex-situ Conservation: This method involves conserving genetic resources outside their natural habitats by maintaining sample populations in facilities like zoos, botanical gardens, wildlife safari parks, and gene banks. Many species extinct in the wild are preserved in zoological parks.
Cryopreservation: A prominent ex-situ technique, cryopreservation involves storing biological materials (seeds, tissue cultures) at extremely low temperatures (e.g., -196°C in liquid nitrogen) through rapid or gradual cooling and dehydration. This preserves viable and fertile gametes of threatened species.
Botanical gardens are vital for biodiversity conservation, with about 1500 gardens worldwide conserving around 80,000 species. Zoos also conserve nearly 3000 mammal, bird, and amphibian species, and gene banks preserve valuable plant materials at risk.
Conservation of biodiversity is a global responsibility. The 1992 Earth Summit in Rio de Janeiro urged nations to take steps for biodiversity conservation. The 2002 World Summit on Sustainable Development in Johannesburg saw 190 countries pledge to significantly reduce biodiversity loss by 2010.
In simple words: India conserves biodiversity through both in-situ (like national parks, hot spots, sacred groves) and ex-situ (like zoos, botanical gardens, cryopreservation) methods, aiming to protect species within their natural habitats or in controlled environments.

🎯 Exam Tip: When discussing conservation efforts, clearly distinguish between in-situ and ex-situ methods and provide examples for each, including international initiatives like Earth Summits.

Question 28. Briefly explain.a. Ex situ conservation b. In situ conservation c. Protected areas d. Biosphere Reserves
Answer:a. Ex situ conservation: This refers to the conservation of genetic resources by preserving them outside their natural habitats. Examples include zoos, botanical gardens, gene banks, and seed banks. b. In situ conservation: This method involves the conservation of genetic resources by maintaining them within their natural ecosystems or original habitats. National parks, wildlife sanctuaries, and sacred groves are examples. c. Protected areas: These are designated land or sea regions managed for the protection and preservation of biodiversity, natural resources, and associated cultural values. d. Biosphere Reserves: These are areas of land and coastal ecosystems that are internationally recognized for their efforts to conserve biodiversity, promote sustainable development, and facilitate scientific research and education, often established under UNESCO's Man and Biosphere Programme.
In simple words: Ex-situ means conserving species outside their natural habitat (like zoos), while in-situ means conserving them within their natural habitat (like national parks). Protected areas are general zones for conservation, and biosphere reserves are large, internationally recognized areas for ecological, social, and economic sustainability.

🎯 Exam Tip: A clear, concise definition distinguishing between conservation strategies is essential for understanding environmental policy.

Question 29. Our wildlife resources are depleting very fast. Suggest possible measures to check the same.
Answer: To address the rapid depletion of wildlife resources, several measures can be implemented:
- Imposing stringent legal penalties against poachers.
- Raising public awareness about the ongoing decline of wildlife populations.
- Protecting entire ecosystems, including National Parks, Sanctuaries, and Biosphere Reserves.
In simple words: To save wildlife, we need strict anti-poaching laws, public awareness, and protection for entire ecosystems.

🎯 Exam Tip: Solutions to environmental problems should be practical and address multiple aspects, including legal, educational, and direct conservation actions.

Question 30. What was the purpose of establishing Jim Corbett National Park?
Answer: Jim Corbett National Park was established with the primary purpose of conserving prominent species like the Tiger, Panther, and Elephant.
In simple words: Jim Corbett National Park was created mainly to protect tigers, panthers, and elephants.

🎯 Exam Tip: Knowing the specific purpose behind the establishment of key national parks demonstrates an understanding of conservation history and priorities.

Question 31. Name the National Parks famous fora. Tiger b. One horned Rhinoceros c. Lion tailed monkey d. Nilgiri Tahr e. Asiatic lion
Answer:a. Tiger: Corbett National Park b. One horned Rhinoceros: Kaziranga National Park c. Lion tailed monkey: Silent Valley National Park d. Nilgiri Tahr: Eravikulam National Park e. Asiatic lion: Gir National Park
In simple words: Different national parks are famous for specific animals they protect, like Corbett for tigers, Kaziranga for rhinos, and Gir for lions.

🎯 Exam Tip: Memorizing national parks and their associated flagship species is a common way to test knowledge in biodiversity conservation.

Question 32. Observe the board and write your opinion.a. Name the animal. b. Give the scientific name of the animal. c. Wildlife is our treasure. Give reason.
ℹ️ चित्र व्याख्या (Diagram Explanation): इस चित्र में एक बोर्ड दिखाया गया है जिस पर लिखा है: "मेरी माँस का कोई औषधीय मूल्य नहीं है, फिर भी मेरा शिकार होता है।" यह संदेश वन्यजीवों के अवैध शिकार के खिलाफ जागरूकता बढ़ा रहा है।
Answer:a. The animal depicted on the board is the Nilgiri Langur, a primate currently facing extinction, primarily found in Silent Valley National Park. Many tribal and local communities mistakenly believe that its flesh possesses medicinal properties for treating various diseases, leading to its hunting for "Rasayanam" preparations. However, its flesh has no proven medicinal value, so it should be left undisturbed. b. Scientific name: *Semnopithecus johnii* (previously known as *Presbytis johnii*). c. Wildlife is indeed our treasure, holding immense importance for humanity due to various values:
- Ecological value: The destruction of wildlife can disrupt the natural ecological balance.
- Commercial value: Fur-bearing animals, elephant ivory, rhinoceros horns, and musk deer glands command high international prices.
- Game value: Wildlife also offers significant game value.
- Scientific value: Wildlife serves as a genetic pool or gene bank vital for breeding programs in agriculture, animal husbandry, and fisheries.
- Aesthetic value: Their inherent beauty and appeal contribute to human aesthetic appreciation.
- Medicinal value: Numerous drugs used to alleviate human suffering are derived from wild plants and animals.
In simple words: The board warns against hunting the Nilgiri Langur (scientific name: *Semnopithecus johnii*), which is wrongly believed to have medicinal value. Wildlife is a treasure because it maintains ecological balance, provides commercial goods, offers scientific resources, and has aesthetic and medicinal benefits.

🎯 Exam Tip: When analyzing such scenarios, combine observation with biological knowledge and ethical considerations, detailing both the problem and the broader implications for conservation.

Question 33. The board you see is placed in front of a National Park. Evaluate the quotation on the board and state your opinion, keeping in mind the need for Biodiversity and Conservation.
ℹ️ चित्र व्याख्या (Diagram Explanation): यह चित्र एक नेशनल पार्क के प्रवेश द्वार पर लगे बोर्ड को दर्शाता है। बोर्ड पर लिखा है, "यादें लेकर जाएँ, कुछ भी पीछे न छोड़ें, केवल अपने पदचिह्न।" यह पार्क में आगंतुकों से प्रकृति का सम्मान करने और न्यूनतम प्रभाव छोड़ने का आग्रह करता है।
Answer: The quotation on the board, "Take nothing except memories; Leave nothing, except your foot prints," effectively encapsulates the ethos of biodiversity conservation within a National Park. My opinion is that this message is vital because it advocates for a "leave no trace" principle, which is fundamental for preserving the integrity of natural ecosystems.
It signifies the following guidelines for visitors:
- Do not approach or disturb any wildlife.
- Do not feed or remove any wildlife from the Arboretum (or park).
- Do not release wildlife into the Arboretum (or park).
- Do not pick flowers, fruits, vegetables, or seeds.
- Do not stand or walk on garden beds.
- Do not litter.
- Do not tease the wildlife.
- Enjoy the wildlife and allow them to live undisturbed in their natural habitat.
- Recognize that wildlife is our treasure and must be properly conserved.
In simple words: The board's message, "Take nothing but memories, leave nothing but footprints," is crucial for National Parks, emphasizing minimal impact, respecting wildlife, and preserving natural beauty for biodiversity conservation.

🎯 Exam Tip: Evaluating such quotes requires relating them to core conservation principles, illustrating how simple guidelines contribute to broader environmental protection goals.

Question 34. Imagine that one day the water on the whole earth disappeared. Give some consequences that we would face.
Answer: The disappearance of all water on Earth would trigger catastrophic consequences. Water scarcity is already a critical global issue, affecting a significant portion of the world's population and projected to worsen. Without water, all life forms-plants, animals, and humans-would perish due to dehydration and the collapse of all ecosystems. Photosynthesis would cease, leading to a complete breakdown of food chains. Global climate patterns would undergo extreme, uninhabitable changes. The absence of water bodies would eliminate all aquatic life and render the planet barren and lifeless, leading to the ultimate extinction of all species.
In simple words: If Earth's water vanished, all life would die from dehydration, ecosystems would collapse, photosynthesis would stop, and the planet would become barren, leading to universal extinction.

🎯 Exam Tip: When describing hypothetical catastrophic scenarios, ensure a comprehensive explanation covering biological, ecological, and climatic impacts.

Question 35. The identified species of all organisms on the earth range between 1.7 to 1.8 million. Global Biodiversity Information Facility and the Species 2000 have identified the number of species in each group of animals.a. Name the group with maximum species identified. b. Name the group with the less species identified. c. Give an approximate number of mammalian species identified.
Answer:a. The group with the maximum identified species is Insects. b. The group with the least identified species is Viruses. c. An approximate number of identified mammalian species is 4,650.
In simple words: Insects have the most identified species, viruses have the least, and about 4,650 mammalian species have been identified globally.

🎯 Exam Tip: Factual recall about species diversity across different taxonomic groups is important; focus on general trends and significant numbers.

Question 36. Observe the following pie diagram and make a write up on the percentage of the threatened species in Amphibia, Birds and Mammals.
ℹ️ चित्र व्याख्या (Diagram Explanation): यह पाई डायग्राम उभयचरों, पक्षियों और स्तनधारियों में लुप्तप्राय प्रजातियों के प्रतिशत को दर्शाता है, जिसमें प्रत्येक समूह में गंभीर रूप से लुप्तप्राय, कमजोर और कम जोखिम वाली प्रजातियों का विभाजन दिखाया गया है।
Answer: The provided pie diagram illustrates the distribution of threatened species across Amphibia, Birds, and Mammals, categorized into Critically Endangered, Vulnerable, and Lower Risk.
In Amphibians: 22% are Critically Endangered, 43% are Vulnerable, and 16% are in the Lower Risk category.
In Birds: 21% are Critically Endangered, 43% are Vulnerable, and 15% are in the Lower Risk category.
In Mammals: 19% are Critically Endangered, 38% are Vulnerable, and 31% are in the Lower Risk category.
Overall, amphibians show the highest percentage of Critically Endangered species (22%), closely followed by birds (21%). Both amphibians and birds have a high proportion of Vulnerable species (43%). Mammals, while having a slightly lower percentage of Critically Endangered (19%) and Vulnerable (38%) species compared to the other two groups, still represent a significant portion of threatened biodiversity, with a notable 31% in the Lower Risk category, indicating continuous monitoring is required.
In simple words: The pie charts show that amphibians and birds have similar high percentages of critically endangered and vulnerable species, while mammals also have significant numbers, emphasizing widespread threat across these groups.

🎯 Exam Tip: When interpreting diagrams, accurately extract percentages for each category and provide a comparative analysis to highlight significant trends or differences between groups.

Question 37. One of the major reasons for extinction of species is the destruction of habitat. Justify this statement by using two examples from your surroundings.
Answer: Habitat destruction is undeniably a primary driver of species extinction. When natural environments are altered or destroyed, species lose their homes, food sources, and breeding grounds, making survival impossible.
For example:
- The extinction of *Rana hexadactyla* (a species of frog) can be directly linked to the destruction of marshlands. Marshes serve as crucial habitats for these frogs, providing breeding sites and food. Their loss leads to the disappearance of the species.
- The decline of local bird populations due to increasing urbanization and the clearing of native trees for construction, which eliminates nesting sites and foraging areas.
In simple words: Habitat destruction is a main cause of extinction, as seen with *Rana hexadactyla* dying out due to marshland destruction and local birds disappearing as urban growth removes their natural nesting and feeding grounds.

🎯 Exam Tip: Justifying a statement with examples strengthens the argument; ensure examples are relevant and clearly illustrate the point.

Question 38. The given bar diagram shows the population size of Rana hexadactyla in the rice fields of Malabar. Observe and analyse the graph.a. Write your findings from the graph b. Predict the population of frogs in the near future c. Enlist the reasons for this effect
ℹ️ चित्र व्याख्या (Diagram Explanation): यह बार डायग्राम मलबार के धान के खेतों में *Rana hexadactyla* (मेंढक की एक प्रजाति) की आबादी के आकार को 1975, 1985, 1995 और 2005 के वर्षों के लिए दर्शाता है। यह मेंढक की आबादी में समय के साथ गिरावट का स्पष्ट रुझान दिखाता है।
Answer:a. Findings from the graph: The bar diagram clearly shows a consistent decrease in the population size of *Rana hexadactyla* in the rice fields of Malabar over the years, from 1975 to 2005. The population was highest in 1975 and steadily declined in subsequent decades. b. Prediction for the near future: Based on the observed trend of continuous decline, it can be predicted that the population of *Rana hexadactyla* will likely face extinction in the near future if current conditions persist. c. Reasons for this effect:
- Habitat destruction
- Excessive use of pesticides
- Change in climate
- Use of agricultural machines
- Excessive killing
In simple words: The graph indicates a steady decline in *Rana hexadactyla* population, suggesting future extinction due to habitat loss, pesticide use, climate change, agricultural machinery, and over-hunting.

🎯 Exam Tip: When analyzing graphs, first describe the trend, then make a logical prediction, and finally list potential causes supported by ecological principles.

Question 1. In the Pie charts (a) and (b) drawn below to show the global animal diversity, which groups of animals would you name and write on the areas shaded black in (a) and (b). In which kind of habitat would you find these groups of animals?a. Invertebrates b. Vertebrates
ℹ️ चित्र व्याख्या (Diagram Explanation): यह चित्र वैश्विक पशु विविधता को दर्शाने वाले दो पाई चार्ट (ए) और (बी) प्रस्तुत करता है। काला छायांकित क्षेत्र विभिन्न पशु समूहों का प्रतिनिधित्व करता है।
Answer:a. The shaded black area in pie chart (a) represents Invertebrates, specifically Insects, which constitute the largest proportion of global animal diversity. These are predominantly found in aerial, terrestrial, and aquatic habitats. b. The shaded black area in pie chart (b) represents Vertebrates, specifically Fishes, which form a significant group within vertebrate diversity. Fishes are exclusively found in aquatic habitats.
In simple words: In pie chart (a), the black area is Insects (invertebrates) found in all habitats; in (b), it's Fishes (vertebrates) found in aquatic habitats.

🎯 Exam Tip: When interpreting pie charts on biodiversity, identify the largest and most distinct categories and associate them with their typical habitats.

Question 2. Amazonian rain forests have the greatest biodiversity on earth. List any two hypotheses that are proposed by the biologists to account for the greater biological diversity.
Answer: Biologists propose several hypotheses to explain the exceptional biodiversity in Amazonian rainforests:
- The Amazonian forests, often called the "Lungs of Planet Earth," maintain consistently stable environments. This environmental stability promotes niche specialization, allowing for a greater diversity of species to coexist by utilizing resources in distinct ways.
- These forests have remained relatively undisturbed for millions of years. This long period of evolutionary time has provided ample opportunity for extensive species diversification, leading to the evolution of many unique life forms.
In simple words: Amazonian rainforests have high biodiversity due to stable environments fostering unique adaptations and millions of years of undisturbed evolution allowing for vast species diversification.

🎯 Exam Tip: When asked for hypotheses, state them clearly and briefly explain the underlying biological reasoning.