Explore topic-wise InterviewSolutions in .

1. There are 39 islands in the Indian Ocean. Most of them are away from the coastline. They are deep sea islands. 

2. The islands of the Indian Ocean are a varied collection, including many smallest territories and some large islands like Sri Lanka, Australia and Madagascar.

The islands in the Indian Ocean are grouped into-

1. Islands of Arabian sea 

2. Islands along Bay of Bengal 

3. Islands along the Australian coast

Islands in Indian Ocean-

1. Islands of the Arabian Sea can be sub grouped such as islands close to the African coast and islands along the Lakshadweep – Chagos Ridge. 

2. The largest island close to the African coast is Madagascar island. It is separated from Africa, and later from the Indo-Australian plate. It is one of the seismologically active provinces. 

3. There are many islands between the eastern coast of Africa and Madagascar island, such as Comoros, Europa and Bassas de India, etc. To the east of Madagascar are Mauritius, Reunion and Seychelles, etc. 

4. The group of islands along Lakshadweep-Chagos Ridge are Maldives, Chagos and Lakshadweep. 

5. Apart from these islands, other islands are the Bundle island near the coast of Pakistan and Siri, Lavan, Kish, Hendorabi, etc., along the Persian Gulf part of Iran.

6. The islands in Bay of Bengal are associated with the converging plate boundary. These islands are the peaks of submerged mountains. The islands of Bay of Bengal are Sri Lanka, Andaman and Nicobar group, and chain of islands along the western coast of Sumatra island of Indonesia. 

7. Most of these islands are volcanic islands. Sri Lanka is the largest island of this group. 

8. There are very few islands along the coastline of Australia such as Cacos, Christmas, Ashmore, etc.

Round yellow seed is the dominant trait.

Wrinkled seed shape is a recessive trait. It expresses only under homozygous condition of alleles.

Reasons for Biodiversity Conservation

▪ There are three main reasons for conserving the biodiversity which have been classified into the following categories:

i. Narrowly utilitarian arguments 

• Human beings derive direct economic benefits from nature, like food, firewood, fibre, construction material, industrial products (resins, gums, dyes, tannins, etc.) and medicinally important products. 

• More than 25 per cent of the drugs are derived from plants and about 25,000 species of plants are used by native people as traditional medicines.

ii. Broadly utilitarian arguments 

• Biodiversity plays a major role in maintaining and sustaining supply of goods and services from various species as well as ecological systems. 

• The different ecological services provided are:

a. Amazon forest is estimated to contribute 20 per cent of the total oxygen in the atmosphere on earth. 

b. Ecosystem provides pollinators like bees, bumble bees, birds and bats which pollinate plants to form fruits and seeds.

iii. Ethical reasons 

• There are thousands of plants, animals and microbes on this earth which are not useless. Every one has some intrinsic value even if it is not of any economic value to us. 

• It is, therefore, our moral duty to ensure well-being of all the living creatures for the utilisation of future generations.

a. lexander von Humboldt. He observed that within a region, species richness increased with increasing explored area but only up to a limit. 

b. 

i. The slopes regression lines are similar when unaffected distribution in an area is analysed.

ii. The slope of regression is steeper when we analyse the species area relationship among very large areas like entire continent. Z (slope of the line) is the regression co-efficient.

c. If species richness is more, i.e., in the range 0.62-1.2.

The phenomenon of failure of cytokinesis after cell division resulting in increase of whole set of chromosome in an organism is called polyploidy.

a. lexander von Humboldt. He observed that within a region, species richness increased with increasing explored area but only up to a limit.

b. 

i. The slopes regression lines are similar when unaffected distribution in an area is analysed.

ii. The slope of regression is steeper when we analyse the species area relationship among very large areas like entire continent.

Z (slope of the line) is the regression co-efficient.

c. If species richness is more, i.e., in the range 0.62-1.2.

The equation of the curve ‘a’ is S = CA^Z .

i. Within a region, species richness increases with increasing explored area but only up to a limit. 

ii. Relationship between species richness and area for a wide variety of taxa turns out to be rectangular hyperbola.

Father : 44 + XY 

Mother : 44 + XX^h 

Son : 44 + X^hY. 

(X^h = X chromosome with gene for haemophilia)

Genetic variation affects the variation in potency and concentration of the drug reserpine in the medicinal plant Rauwolfia.

a → Mammals b → Amphibians

The aggregate of all the genes and their alleles, present in an interbreeding population is known as a gene pool.

(a) sacred groves

All the physical and chemical factors that induce mutation, UV radiation /X rays.

Detailed answer:

All the physical and chemical factors that induce mutation are called mutagens. The physical factors which can be a mutagen are the ionizing radiations like X-rays, gamma rays & the non-ionizing radiations like ultraviolet rays.

Endemic species are native species restricted to a particular geographical region. Exotic species are species which are introduced from other geographical regions into an area.

Physical mutagen—UV rays; Chemical mutagen—5-Bromouracil.

Mutation can be defined as a sudden change in genetic sequence of an individual which may lead to variation of characters.

Agricultural fields like wheat field or paddy field which are also examples of monoculture practices.

The genes which tend to transmit together as a single unit, as they are located very close on the same chromosome, from one generation to the next are called linked genes. The linked genes modify the Mendelian dihybrid ratio from 9 : 3 : 3 : 1 to 3 : 1 and modify dihybrid test ratio from 1 : 1 : 1 : 1 to 1 : 1.

David Tilman found that plots with more species showed less year-to-year variation in total biomass. He also showed that in his experiments, increased diversity contributed to higher productivity.

The genes which tend to transmit together as a unit, as they are located very close on the same chromosome are called linked genes.

Features of a stable community are as follows:

i. Communities should have greater biodiversity for greater stability. 

ii. It should be able to prevent invasion by alien species. 

iii. It should be able to restore itself in a short period of time. 

iv. Variations should be minimal in the community.

Thousand varieties of mangoes represent genetic diversity. 

This is possible because:

i. Single species show high diversity at genetic level over its distributional range. 

ii. Different varieties grow in different geographical areas. 

iii. Mutations.

The occurrence of different types of genes, gene pools, species, habitats and ecosystems in a particular place and various parts of earth is called biodiversity.

i. Genetic diversity 

ii. Genetic diversity

i. Genetic diversity 

ii. Ecological diversity

Yes. The specialities of tropics are They remained undisturbed for millions of years. The tropical environment is less seasonal, more constant and predictable. There is more solar energy, which contribute to higher productivity.

Animals bear nervous system for control and coordination of activities. They also bear receptors to respond to environment stimuli. Many responses become adaptive for survival. Thus animal bears higher species diversity than plants.

1. Narrowly utilitarian argument.

Broadly utilitarian argument.

2. Narrowly utilitarian argument.

3. Zoological parks, botanical gardens, Cryopreservation, tissue culture, seed banks, pollen banks, etc.

(a) Biodiversity 

(b) Exitu conservation – conservation of flora and fauna outside the natural habitat

Insitu conservation- conservation.of flora and fauna in the natural habitat 

(c) Biodiversity hotspots are regions with very high levels of species richness and high degree of endemism Western ghats is the hotspots where accelerated habitat loss occurs.

Insitu conservation- Ms the conservation of plant and animal sp. in natural habitat.
Eg- biosphere reserves, national parks and sanctuaries.
Exitu conservation- It is the conservation of plant and animal sp outside the natural habitat.
Eg- Zoological parks, botanical gardens and wildlife safari parks.

• Genetic diversity
• Species diversity
• Ecosystem diversity

1. Tropics have remained undisturbed for millions of years and had a long evolutionary time for species diversification.

2. Constant and predictable tropical environments promote niche speciation and greater diversity.

3. More solar energy in tropics contributes higher productivity and indirectly to greater diversity.

(i) Habitat loss and fragmentation:

The degradation of many habitats by pollution affects the survival of many species. It results large habitats are broken up into small fragments.

Amazon rain forest is cleared for cultivating soya beans or for conversion to grasslands for raising beef cattle

(ii) Over-exploitation :

It leads to the over exploitation of natural resources. 

For example the extinction of Steller’s sea cow, passenger pigeon was due to humans.

(iii) Alien species invasions : The introduction of foreign species cause the reduction or extinction of indigenous species. 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

(iv) Co-extinctions : If two species are in obligatory relationship the extinction of one species affect the other.

Eg – coevolved plant-pollinator mutualism where extinction of one species leads to the extinction of the other.

(a) yes, For example forest is used for some basic needs of a man but not for clearing of trees . 

(b) Exitu conservation – conservation of flora and fauna outside the natural habitat

Eg - Botanical garden

Insitu conservation – conservation of flora and fauna in the natural habitat

Eg - wild life sanctuaries and national parks

(a) i) Habitat loss and fragmentation 

(ii) Over-exploitation 

(iii) Alien species invasions 

(iv) Co-extinctions

(b) It is through in situ (on site) conservation and ex situ (offsite) conservation

• Genetic diversity
• Species diversity
• Ecological diversity.

1. Genetic diversity – A single species might show high diversity at the genetic level over its distributional range

2. Species diversity – Diversity at species level

3. Ecological diversity – Diversity at ecosystem level

(a) Species richnes decreases from equator to poles. 

(b) Climate is constant and predictable Glaciations were absent. Tropical region get more solar energy.

(c) Habital loss and fragmentation Invansion of alien species.

Agreed with the statement as we have a moral duty to care for their well-being and pass on our biological legacy in good order to future generations.

Protective measures-

Insitu conservation – Biosphere reserve, National park, Wild Life Sanctuary etc.

Exsitu conservation – Zoo, Botanical gardens, seed bank etc.

(a) Genetic, Species, Ecosystem level diversity. 

(b)(i) Habitat loss and fragmentation

(ii) Over exploitation 

(iii) Alien species Invasion 

(iv) Co-extinction etc.

Biodiversity 

▪ The occurrence of different types of genes, gene pools, species, habitats and ecosystems in a particular place and various parts of earth is called biodiversity. 

▪ The term ‘biodiversity’ was given by Edward Wilson. 

▪ Biodiversity is divided into three levels :

i. Genetic diversity 

• It is the measure of variety in genetic information contained in the organisms. 

• It enables a population to adapt to its environment. 

• For example, medicinal plant Rauwolfia vomitoria growing in Himalayan ranges shows variation in potency and concentration of the active chemical reserpine that it produces.

• There are more than 50,000 genetically different strains of rice and 1,000 varieties of mango in India.

ii. Species diversity 

• It is a measure of the variety of species and their relative abundance present within a region. 

• For example, the Western Ghats have a greater amphibian species diversity than the Eastern Ghats. 

iii. Ecological diversity 

• It is a measure of the diversity at community and ecosystem levels. They represent the local, unique habitat and regional components of species diversity. 

• For example, ecological diversity is greater in India due to presence of large number of ecosystems like deserts, rainforests, coral reefs, wetlands, estuaries and alpine meadows.

Biodiversity is a source of hybrids, GM plants, biopesticides, organic farming, bio fertilizer, improved varieties of plants, disease resistant plants.

VNTR - Variable Number Tandem Repeats. 

Probe - is labelled / ratio active (single stranded hybridised DNA fragments).

Detailed answer:

Full forms of VNTR - Variable Number Tandem Repeats.

The VNTR are short nucleotide repeats in DNA which vary in number in different individuals but specific to each individual. while DNA probes are radioactive, labelled, DNA fragments having repeated base sequence complementary to VNTRs. Repressor protein synthesised by i-gene combine with inducer (lactose) to form inactive repressor which does not bind to operator gene and RNA polymerase from promoter gene moves to the structural genes to help in transcription. In the absence of lactose, repressor binds to the operator gene which is switched off and RNA polymerase cannot move from promoter gene and thus there is presence of lactose in the cell, regulates activation or inactivation of the lac operon and is termed inducer.

UAA, UAG and UGA.

It catalyses the attachment of amino acid to tRNA.

Correct option is a. 40 mL

Correct option is a. 40 mL

Correct option is a. 40 mL