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Q1. What is the function of National Bureau of Plant Animal and Fish Genetic Resources? 

Solution

The main function of National Bureau of Plant Animal and Fish Genetic Resources is to collect and conserve the germplasm of plants and animals in seed gene banks and field gene banks.

Q2. Explain giving one example, how co-extinction is one of the causes of loss of biodiversity. List the three other causes also. 

Solution

When a species becomes extinct, the plant and animal species associated with it in an obligatory may also become extinct. This is called co-extinction. For example, when a host fish species becomes extinct, its unique assemblage of parasites also becomes extinct. Three other causes are- (a) Habitat loss and fragmentation (b) Over-exploitation (c) Alien species invasion

Q3. (i) What is biodiversity? Why is it a matter of concern now? (ii) Satish heard about red data book in a TV programme on conservation of natural resources. He wanted to know in detail about this book so he discussed it with biology teacher who explained to him about this. Read the above passage and answer the following questions: (a) What is Red Data Book? (b) What is the utility of this document? (c) Who publishes this book?

Solution

(i) Biodiversity is the occurrence of different types of genes, gene pools, species, habitats and ecosystems in a particular space and various parts of earth. It is a matter of concern because species are continuously lost, limiting the diversity and this will affect our survival and well-being on earth due to the changes in environment. (ii) (a) Red Data Book is a document in which the lists of species are published whose continued existence is threatened.  (b) The basic utility is to create awareness about the importance of threatened biodiversity and to identify the endangered species. (c) International Union of Conservation of Nature and Natural Resources (IUCN) publishes the Red Data Book. Now IUCN is called World Conservation Union.

Q4. Write the major causes of biodiversity losses.

Solution

The major causes of biodiversity losses are- (a) Habitat loss and fragmentation (b) Over-exploitation (c) Alien species invasions (d) Co-extinctions

Q5. Define biodiversity. Write three forms of biodiversity.

Solution

Biodiversity is the vast array of species of living organisms occurring on the earth and the ecological complexes. Three forms of biodiversity are alpha diversity, beta diversity and gamma diversity.

Q6. What is the ecological importance of biodiversity?

Solution

The ecological importance of biodiversity are- (a)Biodiversity is required for maintaining and sustainable use of goods and services from ecosystem. (b) Various insects help in pollination. (c) Various micro-organisms help in the decomposition of organic matter thereby increasing the soil fertility. (d) Various drugs and medicines are extracted from plants.

Q7. India has more than 50,000 strains of rice. Mention the level of biodiversity it represents.

Solution

50,000 strains of rice represent species biodiversity because the strains represent variety of species and their relative abundance. 

Q8. Write a note on biodiversity conservation. 

Solution

The scientific management and preservation of flora and fauna in its natural form is called biodiversity conservation. There are two types of conservation strategies: in situ conservation, which is the protection of species in their natural habitat (national parks), and ex situ conservation, which is the protection of species in an artificially created habitat (botanical garden).

Q9. Why is genetic variation important in the plant Rauwolfia vomitoria?

Solution

Genetic variation affects the production of the drug reserpine in the medicinal plant Rauwolfia.

Q10. Explain the efforts for the conservation of biodiversity at international level.

Solution

(i) The Earth Summit was held at Rio de Janeiro (Brazil) in which representatives of more than 170 countries were present. The summit promoted Convention on Biological Diversity (CBD). India became a member of this convention in May 1994. The important objectives were- (a) Finding and supporting various methods to conserve biological diversity. (b) Use of biodiversity only up to sustainable limit. (c) The benefits derived from use of genetic resources should be fairly and equitably shared. (ii) A second World Summit on biological diversity was held in 2002 in Johannesburg in which 190 countries pledged to reduce the current rate of biodiversity loss at global, regional and local levels by 2010. (iii) Indian government passed the Biodiversity Bill in December 2003 to protect India’s biodiversity. (iv) Government of India has also established a Biodiversity Board at Chennai to ensure proper utilization of biodiversity. (v) Organizations like World Wildlife Fund (WWW) and World Conservation Union (WCU) provide financial assistance for conservation programmes.

Q11. What do you mean by conservation of biodiversity? What are its objectives?

Solution

Conservation may be defined as a technique of deriving maximum advantages from the biosphere without degrading its conservation. The three main objectives are- (a) To maintain essential ecological processes and life supporting systems like air, water and soil. (b) To preserve the diversity of species and the range of genetic material of world’s organisms. (c) To ensure a continuous use of species and ecosystem this will support the rural communities and urban industries.

Q12. While going to Nainital during summer vacations, Amitabh saw a board indicating the direction to Jim Corbett National Park. He asked his uncle, who happened to be a forest officer, about national parks. He explained that national parks are maintained by government solely for the welfare of entire wild life in it. Read the above passage and answer the following questions: (a) How is wild life maintained in a national park? (b) Name two other national parks. (c) What value is displayed by Amitabh’s uncle?

Solution

(a) In a national park, some land is allowed for wildlife conservations and habitat manipulation is not permitted in this zone. Cultivation and grazing is also not allowed. (b) Two national parks are Bandipur National Park and Hazaribagh National park. (c) Amitabh’s uncle had a sound knowledge of wildlife conservation that he provided to his nephew, which is important for our life.

Q13. Alien species are a threat to native species. Justify taking examples of an animal and a plant alien species.

Solution

The species that have been introduced from another geographic region to an area outside its natural range are called alien species or exotic species. For example (i) Parthenium, Lantana and Eicchornia are the alien species of plants that have invaded the native species of India and caused environmental damage. (ii) Introduction of African catfish Clarias gariepinus for aquaculture purpose is posing threat to many indigenous catfish. (iii) Nile perch introduced into lake Victoria in East Africa led to the extinction of cichlid fish.

Q14. What does the term genetic diversity refer to? What is the significance of large genetic diversity in a population? 

Solution

Genetic diversity is the measure of variety in genetic information contained in the organisms. The significance of large genetic diversity in a population are- (a) Larger genetic diversity provides adaptability at the time of environmental changes and helps the species in surviving. (b) Larger genetic diversity is also useful in the evolution of species.

Q15. Biodiversity must be conserved as it plays an important role in many ecosystem services that nature provides. Explain any two services of the ecosystem.

Solution

The two services of the ecosystem are- (a) Forest ecosystem purifies air, mitigate droughts and floods. (b) The cycling nutrients generate fertile soil and maintain biodiversity.

Q16. What are seed banks?

Solution

The collections of seeds of many different genetic strains of commercially important plants that are kept viable for longer periods in place are called seed banks.

Q17. Why are (i) alien species invasion and (ii) loss of habitat and fragmentation considered to be the major cause of loss of biodiversity? Explain with the help of one example each.

Solution

(i) The alien species became invasive and caused extinction or decline of indigenous species. For example, the Nile perch introduced into Lake Victoria in East Africa led to the extinction of more than 200 species of cichlid fish in the lake. (ii) Loss of habitat and fragmentation drive animals and plants to extinction. For example, as the Amazon forest is cut and cleared for cultivating soya beans or for conversion of grasslands for raising beef cattle by which many species are affected.

Q18. What are endangered species? How many animals and plants are endangered in India?

Solution

A species is endangered when its populations have decreased or habitats have been reduced to the levels that pose immediate danger of extinction. They are not likely to survive if the factors threatening their extinction continue. 54 animals and 113 plants are endangered in India.  

Q19. What is cryopreservation? Write the importance of cryopreservation in conservation of biodiversity.

Solution

Cryopreservation is a technique of preserving sperms, eggs, animal cells, tissues and embryos at very low temperature of around -196 degree centigrade in liquid nitrogen. By cryopreservation, the reproductive parts of rare species can be preserved.

Q20. Name the Indian hotspots that extend into other countries.

Solution

The hotspots of India that extend into other countries are Western Ghats- Sri Lanka and Indo-Burma-Himalayas.