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Correct Answer is: (d) A and C

The project ensures a viable population of Bengal tigers in their natural habitats, protecting them from extinction and preserving areas of biological importance as a natural heritage.

A sacred grove or sacred woods are any grove of trees that are of special religious importance to a particular culture. Sacred groves feature in various cultures throughout the world.

(b) Tropical forest

Exotic species are organisms often introduced unintentionally or deliberately for commercial purpose, as biological control agents and other uses. They often become invasive and drive away the local species and is considered as the second major cause for extinction of species. Exotic species have proved harmful to both aquatic and terrestrial ecosystems. Tilapia fish (Jilabi kendai) (Oreochromis mosambicus) introduced from east coast of South Africa in 1952 for its high productivity into Kerala’s inland waters, became invasive, due to which the native species such as Puntius dubius and Labeo kontius face local extinction.

Amazon rain forest is known as the “lungs of the planet” since a great proportion of CO released due to anthropogenic activities are uptaken by their dense tropical forests, which is homologous to the functioning of human beings except for the difference in gases.

Habitat fragmentation is the process where a arge, continuous area of habitat is both, reduced in area and divided into two or more fragments. Fragmentation of habitats like forest land into crop lands, orchard lands, plantations, urban areas, industrial estates, transport and transit Systems has resulted in the destruction of complex interactions amongst species, (food chain and webs) destruction of species in the cleared regions, annihilation of species restricted to these habitats (endemic) and decreased biodiversity in the habitat fragments. Animals requiring large territories such as mammals and birds are severely affected.

The elephant corridors and migratory routes are highly vulnerable. The dwindling of many well-known birds (sparrows) and animals can be attributed to this.

1. Endemism : A species or a taxon which is confined to a specific area 

2. E.g: Nilgiri Thar

Red Data book or Red list is a catalogue of taxa facing risk of extinction. IUCN – International Union of Conservation of Nature and Natural Resources, which is renamed as WCU – World Conservation Union (Morges Switzerland) maintains the Red Data book. The concept of Red list was mooted in 1963. 

The purpose of preparation of Red List are:

• To create awareness on the degree of threat to biodiversity
• Identification and documentation of species at high risk of extinction
• Provide global index on declining biodiversity
• Preparing conservation priorities and help in conservation of action
• Information on international agreements on conservation of biological diversity Red list has eight categories of species.

1. Extinct 

2. Extinct in wild 

3. Critically Endangered 

4. Endangered 

5. Vulnerable 

6. Lower risk 

7. Data deficiency 

8. Not evaluated

(c) Amphibians

India encloses 4 biodiversity hotspots. They are 

1. Himalayan 

2. Indo-Burma 

3. Western ghats 

4. Sundalands

(a) In-situ conservation

In-situ conservation

1. Conservation of plants and animals in their natural habitat. 

2. Example: National parks

Ex-situ conservation

1. Conservation of selected or rare plants or animals in place outside their natural habitat.

2. Example: Off site collections.

Correct Answer is: (c) Ten

Gangetic Plains: These plains are relatively homogenously defined by the Ganges river system and occupy about 11% of the country’s landmass. This region is very fertile and extends up to the Himalayan foothills. Fauna includes rhinoceros, elephant, buffalo, swamp deer, hogdeer.

Ex-situ conservation of selected rare plants/ animals in places outside their natural homes. It includes offsite collections and gene banks.

1. Conservation of animals in their natural habitat is called in-site conservation. 

2. E.g National parks.

(a) Both Assertion and Reason are true and Reason explains Assertion correctly.

A keystone species is an organism that helps define an entire ecosystem. Without the keystone species a particular ecosystem would be dramatically disturbed or even ceased. Keystone species either directly or indirectly affects every species in a particular ecosystem. If a keystone species is lost or removed no other organism would compensate its ecological niche.

Example: Jaguar is a keystone species. As a top predator, it plays a crucial role in ecosystem. Without jaguar there is an exponential increase in herbivoral population that would decimate the plants of the ecosystem. At one point even the herbivore populations also get declined due to the lack of vegetation. Thus jaguar acts a keystone species.

1. Genetic Diversity 

2. Species Diversity 

3. Community / Ecosystem Diversity

1. A species which has been categorized as very likely to become extinct. 

2. Example: Bengal tiger, Polar bears.

Natural habitats are destroyed for the purpose of settlement, agriculture, mining, industries and construction of highways. As a result species are forced to adapt to the changes in the environment or move to other places. If not, they become victim to predation, starvation, disease and eventually die or results in human animal conflict.

1. identify and protect all threatened species 

2. identify and conserve in protected areas the wild relatives of all the economically important organisms 

3. identify and protect critical habitats for feeding, breeding, nursing, resting of each species 

4. resting, feeding and breeding places of the organisms should be identified and protected. 

5. Air, water and soil should be conserved on priority basis 

6. Wildlife Protection Act should be implemented

Ex-Situ Conservation : It is conservation of selected rare plants/ animals in places outside their natural homes. It includes offsite collections and gene banks. Offsite Collections: They are live collections of wild and domesticated species in Botanical gardens, Zoological parks, Wildlife safari parks, Arborata (gardens with trees and shrubs). The organisms are well maintained for captive breeding programmes.

As a result, many animals which have become extinct in the world continue to be maintained in Zoological Parks. As the number increases in captive breeding, the individuals are selectively released in the wild. In this way the Indian crocodile and gangetic dolphin have been saved from extinction.

Gene Banks: Gene banks are a type of biorepository which preserve genetic materials. Seeds of different genetic strains of commercially important plants can be stored for long periods in seed banks, gametes of threatened species can be preserved in viable and fertile condition for long periods using cryopreservation techniques. However, it is not economically feasible to conserve all biological wealth and all the ecosystems. The number of species required to be saved from extinction far exceeds the conservation efforts.

1. Himalayas 

2. Indian deserts 

3. Trans-Himalayan region 

4. Western ghats.

There is a decrease in biodiversity as we move from tropics towards poles due to drop in temperature which makes the condition unfavourable for majority of organisms to survive.

The major causes for biodiversity decline are: 

1. Habitat loss, fragmentation and destruction (affects about 73% of all species),

2. Pollution and pollutants (smog, pesticides, herbicides, oil slicks and GHGs). 

3. Climate change. 

4. Introduction of alien/exotic species. 

5. Over exploitation of resources (poaching, indiscriminate cutting of trees, over fishing, hunting and mining).

6. Intensive agriculture and aquacultural practices. 

7. Hybridization between native and nonnative species and loss of native species 

8. Natural disasters (Tsunami, forest fire, earth quake and volcanoes). 

9. Industrialization, Urbanization, infrastructure development, Transport – Road and Shipping activity, communication towers, dam construction, unregulated tourism and monoculture are common area of specific threats.

10. Co-extinction

1. Tilapia fish (Oreochromis mosambicus) 

2. African Apple snail (Achatina fulica)

1. Natural extinction: It is a slow process of replacement of existing species with better adapted species due to changes in environmental conditions, evolutionary changes, predators and diseases. A small population can get extinct sooner than the large population due to inbreeding depression (less adaptivity and variation) 

2. Mass extinction: The Earth has experienced quite a few mass extinctions due to environmental catastrophes. Amass extinction occurred about 225 million years ago during the Permian, where 90% of shallow water marine invertebrates disappeared.

3. Anthropogenic extinctions: These are abetted by human activities like hunting, habitat destruction, over exploitation, urbanization and industrialization. Some examples of extinctions are Dodo of Mauritius and Steller’s sea cow of Russia. Amphibians seem to be at higher risk of extinction because of habitat destruction. The most serious aspect of the loss of biodiversity is the extinction of species. The unique information contained in its genetic material (DNA) and the niche it possesses are lost forever

In shifting cultivation, plots of natural tree vegetation are burnt away and the cleared patches 1 are farmed for 2-3 seasons, after which their fertility reduces to a point where crop production is no longer profitable. The farmer then abandons this patch and cuts down a new patch of fqrest trees elsewhere for crop production.This system is practiced in northeastern regions of India. When vast areas are cleared and burnt, it results in loss of forest cover, pollution and discharge of CO , which in turn attributes to loss of habitat and climate change which has an 1 impact on the faunal diversity of that regions.

(b) Walter Rosen

Habitat loss, fragmentation and destruction.

1. Natural Extinction 

2. Mass Extinction 

3. Anthropogenic Extinction

The argument of trigonometrical function, i.e., angle is dimensionless. 

Now,

(i) The argument, \([\frac{2\pi t}{T}]=\frac{[T]}{[T]}\) = 1 = [L⁰M⁰T⁰]

which is a dimensionless quantity.

Hence, formula (i) is correct.

(ii) The argument,

[vt] = [LT^-1] [T] = [L] = [L¹M⁰T⁰]

which is not a dimensionless quantity.

Hence, formula (ii) is incorrect.

(iii) The argument,

\([\frac{t}{a}]=\frac{[T]}{[L]}\) = [L^-1M⁰T¹]

which is not a dimensionless quantity.

Hence, formula (iii) is incorrect.

(iv) The argument,

\([\frac{2\pi t}{T}]=\frac{[T]}{[T]}\) = 1 = [L⁰M⁰T⁰]

which is a dimensionless quantity.

Hence, formula (iv) is correct.

Human activities, both directly and indirectly are today’s main reason for habitat loss and biodiversity loss. Fragmentation and degradation due to agricultural practices, extraction (mining, fishing, logging and harvesting) and development (settlements, industrial and associated infrastructures) leads to habitat loss and fragmentation leads to formation of isolated, small and scattered populations and as endangered species.

Some of the other threats include specialised diet, specialized habitat requirement, large size, small population size, limited geographic distribution and high economic or commercial value. Large mammals by virtue of their size require larger areas to obtain the necessities of life – food, cover and mates than do smaller mammals. Individual home range of Lion can be about 100 square Km. Mammals have specialized dietary needs such as carnivores, frugivores and the need to forage over much larger areas than general dietary herbivores and omnivores. Mammals also have low reproductive output other than small rodents

Another example for co-extinction is the connection between Calvaria tree and the extinct bird of Mauritius Island, the Dodo. The Calvaria tree is dependent on the Dodo bird for completion of its life cycle. The mutualistic association is that the tough homy endocarp of the seeds of Calvaria tree are made permeable by the actions of the large stones in birds gizzard and digestive juices thereby facilitating easier germination. The extinction of the Dodo bird led to the imminent danger of the Calvaria tree coextinction.

1. Himalayas

2. Western ghats 

3. Indo-Burma region

4. Sundaland

Loss of biodiversity has a immense impact on plant and animal life. The loss of diversity leads to,

1. Extinction of species 

2. Dramatic influence on food chain and food web in. It will lead to immediate danger for food necessity

Temperature, precipitation, distance from the equator (latitudinal gradient), altitude from sea level (altitudinal gradient) are some of the factors that determine biodiversity distribution patterns

(b) Statement 1 is correct, statement 2 in incorrect

(b) y = a sin vt.

(c) y = (a/T)sin(t/a)

Direct and indirect human activities have a detrimental effect on biodiversity. Direct human , activities like change in local land use, species introduction or removal, harvesting, pollution and climate change contribute a greater pressure on loss of biodiversity. Indirect human drivers include demographic, economic, technological, cultural and religious factors.

(a) (P – Q)/R

(e) (R + Q)/P

The term biodiversity was coined by Walter Rosen (1986). The levels of biodiversity are – Genetic diversity, Species diversity and ecosystem diversity

(a) Mass of electron (me)

(b) Universal gravitational constant (G)

(d) Mass of proton (m^p)

(d) When none of its members are alive anywhere in the world.

India has different climate and topography in different parts and hence is termed as a mega diversity country. India occupies 10th place among plant rich countries of the world.

• It is essential to acquire knowledge about the distribution and environmental
• interaction of flora and fauna of India. Biogeographers have classified India into ten bio-geographic zones with each zone
• having characteristic climate, soil and biodiversity

These zones are described below:

1. The cold mountainous snow covered Trans Himalayan region of Ladakh.

2. The Himalayan ranges and valleys of Kashmir, Himachal Pradesh, Uttarakhand, Assam and other North Eastern States.

3. The Terai, the lowland where the Himalayan rivers flow into the plains.

4. The Gangetic and Bhramaputra plains.

5. The Thar Desert of Rajasthan.

6. The semi arid grassland region of the Deccan plateau Gujarat, Maharashtra, Andra Pradesh, Karnataka and Tamil Nadu.

7. The Northeast States of India,

8. The Western Ghats in Maharashtra, Karnataka and Kerala.

9. The Andaman and Nicobar Islands.

10. The long western and eastern coastal belt with sandy beaches, forests and mangroves.

FUNCTIONS OF BIODIVERSITY: Two main functions of biodiversity are

1. It is the source on which the entire human species depends on for food, fibre, shelter, fuel and medicine.

2. It depends on biosphere which in turn leads to stability in climate, water, soil, air and overall health of biosphere.

Walter Rosen.

A species is considered to be locally extinct when it is no longer found in an area it once inhabited but is still found elsewhere in the wild.

(c) North – East India