1. Multiple choice questions.
(i) Conservation of biodiversity is important for:
(a) Animals
(b) Animals and plants
(c) Plants
(d) All organisms
Answer: (d) All organisms
Explanation: Conservation of biodiversity is essential for the well-being of all organisms, including animals, plants, and microorganisms. Biodiversity maintains ecosystem services, genetic diversity, and ecological balance, contributing to the sustainability of life on Earth.
(ii) Threatened species are those which:
(a) threaten others
(b) Lion and tiger
(c) are abundant in number
(d) are suffering from the danger of extinction
Answer: (d) are suffering from the danger of extinction
Explanation: Threatened species are those facing a high risk of extinction. They experience critical population declines due to factors like habitat loss, pollution, and climate change, putting them in danger of disappearing from the planet.
(iii) National parks and sanctuaries are established for the purpose of:
(a) Recreation
(b) Hunting
(c) Pets
(d) Conservation
Answer: (d) Conservation
Explanation: National parks and sanctuaries are established primarily for the purpose of conservation. These protected areas provide safe havens for wildlife, preserve natural habitats, and allow ecosystems to thrive while minimizing human disturbance.
(iv) Biodiversity is richer in:
(a) Tropical Regions
(b) Polar Regions
(c) Temperate Regions
(d) Oceans
Answer: (a) Tropical Regions
Explanation: Biodiversity is typically richer in Tropical Regions due to favorable conditions, such as consistent warmth, abundant resources, and longer periods of evolutionary time, which support a wide variety of species.
(v) In which one of the following countries, the ‘Earth Summit’ was held?
(a) the UK
(b) Mexico
(c) Brazil
(d) China
Answer: (c) Brazil
Explanation: The ‘Earth Summit’ (United Nations Conference on Environment and Development) took place in Brazil in 1992. It aimed to address global environmental challenges and promote sustainable development on an international scale.
2. Answer the following questions in about 30 words.
(i) What is biodiversity?
Answer: Biodiversity refers to the variety of life forms found on Earth, encompassing the diversity of species, ecosystems, and genetic variation within species. It includes the interactions between different organisms and their environments.
(ii) What are the different levels of biodiversity?
Answer: Biodiversity is categorized into three levels: species diversity (variety of species in a region), ecosystem diversity (diversity of ecosystems), and genetic diversity (variation within species at the genetic level).
(iii) What do you understand by ‘hotspots’?
Answer: ‘Hotspots’ are regions with exceptionally high levels of biodiversity and endemic species, facing significant threats due to habitat destruction and human activities. Conservation efforts often focus on these areas to protect unique and endangered species.
(iv) Discuss briefly the importance of animals to human kind.
Answer: Animals provide essential ecosystem services such as pollination, nutrient cycling, and pest control. They contribute to human livelihoods through agriculture, medicine, and tourism. Animals also hold cultural and aesthetic value and play a vital role in maintaining biodiversity.
(v) What do you understand by ‘exotic species’?
Answer: ‘Exotic species’ (also called invasive or non-native species) are species introduced to an area where they are not native. These species can disrupt ecosystems, outcompeting native species and causing ecological imbalances, economic losses, and environmental harm.
3. Answer the following questions in about 150 words.
(i) What are the roles played by biodiversity in the shaping of nature?
Answer: Biodiversity plays fundamental roles in shaping nature and maintaining the health of ecosystems. It ensures ecological balance, contributes to nutrient cycling, and supports various ecosystem services. Biodiversity influences processes like pollination, soil fertility, water purification, and pest regulation. Additionally, it enhances resilience against environmental changes and provides genetic resources for adaptation. Biodiversity’s interactions create intricate webs of life, influencing the stability and functioning of ecosystems.
(ii) What are the major factors that are responsible for the loss of biodiversity? What steps are needed to prevent them?
Answer: Major factors causing biodiversity loss include habitat destruction, pollution, overexploitation, invasive species, and climate change. To prevent loss, actions like habitat conservation, sustainable resource management, pollution control, wildlife protection, and climate change mitigation are crucial. Strengthening protected areas, promoting sustainable practices, enforcing wildlife laws, restoring degraded habitats, and raising awareness are necessary steps. International collaboration, research, and public engagement are vital for addressing these challenges and ensuring the persistence of diverse life forms and the services they provide to ecosystems and humanity.
