1. Multiple choice questions.
(i) Conservation of biodiversity is important for :
(a) Animals (c) Plants (b) Animals and plants (d) All organisms
(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
(iii) National parks and sanctuaries are established for the purpose of :
(a) Recreation (b) Hunting (c) Pets (d) Conservation
(iv) Biodiversity is richer in :
(a) Tropical Regions (b) Polar Regions (c) Temperate Regions (d) Oceans
(v) In which one of the following countries, the ‘Earth Summit’ was held?
(a) the UK (b) Mexico (c) Brazil (d) China
2. Answer the following questions in about 30 words.
(i) What is biodiversity?
Ans. Biodiversity is a combination of two words, Bio (life) and diversity (variety). In simple terms, biodiversity is the number and variety of organisms found within a specified geographic region. It refers to the varieties of plants, animals and micro-organisms, the genes they contain and the ecosystems they form.
(ii) What are the different levels of biodiversity?
Ans. Biodiversity can be discussed at three levels : (i) Genetic diversity; (ii) Species diversity; (iii) Ecosystem diversity.
(iii) What do you understand by ‘hotspots’?
Ans. Areas rich in species diversity are called hotspots. These are regions of the world where attention is needed to address biodiversity loss and begin conservation.
(iv) Discuss briefly the importance of animals to human kind.
Ans. Animals are very important to human beings, in fact even more than plants. Here are some of the points how animals help humans:-
1. Animals provide milk. Milk is an essential dietary need for humans.
2. Hair from animals is used to make clothes, wool, blanket, sweater etc. Which protects humans from harsh weather conditions.
3. Some animals have medicinal molecule which is beneficial for humans. Example heparin an anti-coagulant is used to control clots in blood is obtained from ox lungs and pig intestines.
4. Animals are eaten for food as they contain healthy nutrients for human
Animals are also used for agriculture, transportation and security purposes like ox, cow, horses, elephant, camels, dogs etc.
5. Animals are also part human’s daily recreational plan. It is believed that animals like dog, cat has the tendency to provide relief to many chronic illnesses.
6. Animals dung is used as manure in agricultural fields.
7. Animals are also part of education and other scientific experiments.
(v) What do you understand by ‘exotic species’?
Ans. Species which are not the natural inhabitants of the local habitat but are introduced into the system, are called exotic species. They are also known as alien species, invasive species, introduced species, non-indigenous species.
3. Answer the following questions in about 150 words.
(i) What are the roles played by biodiversity in the shaping of nature?
Ans. Biodiversity has contributed in many ways to the development of human culture. Biodiversity plays the following roles: ecological, economic and scientific.
Ecological Role of Biodiversity:- Every organism capture / store energy, produce and decompose organic materials. That’s how recycling of the nutrients occur throughout the ecosystem. These functions are important for every organism including human survival. The more diverse an ecosystem, better are the chances for the species to survive through adversities and attacks. In other words, the more the variety of species in an ecosystem, the more stable the ecosystem is likely to be.
Economic Role of Biodiversity:- The economic role of biodiversity has to do with benefiting the food manufacturing industries, pharmaceutical and cosmetic industries. Some of the important economic commodities that biodiversity supplies to humankind are: food crops, livestock, forestry, fish, medicinal resources, clothes etc. Hence, we can say that biodiversity is a large pool of resources from where the human beings draw plenty of important things which are helpful in their day-to-day life.
Scientific Role of Biodiversity:- From scientific perspective, biodiversity helps us in understanding how life functions. There are many potential uses of unknown plants, animals, or micro organisms in the form of New medicines, foods, chemicals, and genes are there to be discovered. One fine example is the discovery of GMO (genetically modified organism), wherein genes of plants and animals can be biologically manipulated with a specific desired trait.
(ii) What are the major factors that are responsible for the loss of biodiversity? What steps are needed to prevent them?
Ans. The major factors that are responsible for the loss of biodiversity are:-
1. Increase in the rate of consumption of natural resources due to growth in human population.
2. Over exploitation of resources and deforestation to fulfill the needs of large population.
3. Change in biodiversity due to natural calamities such as earthquakes, floods, volcanic eruptions, forest fires, droughts, etc. cause damage to the flora and fauna of the earth,
4. Pesticides and other pollutants such as hydrocarbons and toxic heavy metals destroy the weak and sensitive species.
5. Introduction of alien species, invasive species, introduced species, non-indigenous species causes extensive damage to the regional ecosystem.
6. Hunting and poaching of certain type of some animals like tigers, elephants, rhinoceros, crocodiles, minks and birds have led to their extinction.
Steps that are needed to prevent loss of biodiversity:-
1. Efforts should be make to protect the species that are endangered.
2. Prevention of extinction requires proper planning and management.
3. Varieties of food crops, forage plants, timber trees, livestock, animals and their wild relatives should be preserved.
4. Each country should identify habitats of wild relatives and ensure their protection.
5. Habitats where species feed, breed, rest and nurse their young should be safeguarded and protected.
6. International trade in wild plants and animals be regulated.