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Levels of biodiversity - class-X

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Select the incorrect statement.

  1. Species diversity increases as we move away from the equator towards the poles.

  2. Stellar's sea cow and passenger pigeon got extinct due to over exploitation by man.

  3. Lantana and Eichhornia are invasive weed species in India.

  4. Among animals, insects are the most species-rich taxonomic group.


Correct Option: A
Explanation:

Species diversity decreases as we move away from the equator towards the poles due to:-

(i)Temperature decreases and conditions become harsh.
(ii)Both the amount and intensity of solar radiation decrease.
(iii)Vegetation decreases.
(iv)Fewer resources available to support species.

So the correct option is 'Species diversity increases as we move away from the equator towards the poles.'

India has a greater ecosystem diversity than a Scandinavian country like Norway. What kind of diversity does it represent?

  1. Species diversity

  2. Ecological diversity

  3. Genetic diversity

  4. None of these.


Correct Option: B
Explanation:

Ecological diversity is the diversity at ecosystem level. India with its deserts, rainforests, mangroves, coral reefs, wetlands, estuaries and alpine meadows has a greater ecosystem diversity than a  Scandinavian country like Norway.

India constitutes _______ percent of the world's land area and contributes _______ percent of the global species diversity.

  1. 1.0, 5.5

  2. 5.5, 1.0

  3. 8.1, 2.4

  4. 2.4, 8.1


Correct Option: D
Explanation:

Although India has only 2.4 percent of the world's land area, its share of the global species diversity is an impressive 8.1 percent. 

Species diversity ______ as we move away from the ______ towards_____.

  1. decreases, equator, poles

  2. increases, equator, poles

  3. decreases, poles, equator

  4. none of these.


Correct Option: A
Explanation:

The biodiversity shows a latitudinal and altitudinal gradient. The species diversity decrease as well as we move away from the equator towards the poles with very few exceptions, tropics harbour more species than temperature or polar areas.

Which of the following statements regarding the estimates of number of species found on earth is not correct?

  1. Total number of species present on earth are considered to be about 7 million as estimated by Robert May.

  2. Plants constitute more than 70% of all the species recorded, whereas animals constitute less than 22% of the total number of species.

  3. Insects constitute more than 70% of all the animal species.

  4. None of these.


Correct Option: B
Explanation:

Animals constitute more than 70% of all the species recorded whereas plants constitute around 22% of total number of species. 

The diversity of organisms sharing the same habitat or community is termed as

  1. alpha diversity

  2. beta diversity

  3. gamma diversity

  4. delta diversity.


Correct Option: A
Explanation:

Ecological diversity is of three types:
(i) Alpha diversity
(ii) Beta diversity
(iii) Gamma biodiversity.

Species diversity ______ as one moves from high to low altitudes.

  1. increases

  2. decreases

  3. first increases then decreases

  4. first decreases then increases


Correct Option: A
Explanation:

Biodiversity changes with the change in altitude. It increases as one moves from higher to lower altitudes.

Alpha diversity is biodiversity present 

  1. within community

  2. between communities

  3. ranges of communities

  4. none of these.


Correct Option: A
Explanation:

Ecological diversity is of three types:
(i) Alpha diversity
(ii) Beta diversity
(iii) Gamma biodiversity.

Study the given populations and choose the correct answer in relation to species diversity.

Population Species  Group Individuals
Population  A                I Mammals  3
     II Birds  2
     III Amphibians  2
Population  B      I Mammals  2
     II Mammals  2
    III Amphibians  1
Population  C      I Mammals  3
    II Mammals  2
   III Mammals  1

 

  1. Maximum diversity - Population B; 

    Minimum diversity - Population C

  2. Maximum diversity - Population A; 

    Minimum diversity - Population C

  3. Maximum diversity - Population A; 

    Minimum diversity - Population B

  4. Maximum diversity - Population B; 

    Minimum diversity - Population A


Correct Option: B
Explanation:

Species diversity is the number of different species present in a given population i. e. 'Species diversity relates to the number of different species.'
In population A, there are 3 different classes present. These are mammals, birds, and amphibians. Hence, it will have vast species diversity.
In population B, only 2 classes are present, namely mammals and amphibians. Hence, species diversity will be less compared to that of population A.
In population C, all the species belongs only to class mammals. Hence, it will show the least species diversity.

So the correct answer is option B.

On a logarithmic scale, the species area relationship is a straight line described by the equation log S = log C + Z log A.
What does S, C, Z and A represent in the given equation? Select the correct answer from the codes given below.
Species richness = 1
Slope of the line  = 2
Y- intercept          = 3 
Area                    = 4

  1. 1 - C; 2 - S; 3 - Z; 4 - A

  2. 1 - S; 2 - Z; 3 - C; 4 - A

  3. 1 - Z; 2 - S; 3 - C; 4 - A

  4. 1 - A; 2 - C; 3 - S; 4 - Z


Correct Option: B
Explanation:

The relationshipbetween species richness and area is rectangular hyperbola for a wide variety of taxa whether they are birds, bats, freshwater fishes or flowering plants and the equation can be given as S = $CA^z$.

Niche overlap indicates 

  1. mutualiism between two species

  2. active cooperation between two species

  3. two different parasites on the same host

  4. sharing of one more resources between the two species


Correct Option: D
Explanation:

Ecological niche means the total interaction of a species with its environment or its functions position on status in an ecosystem. Ecological niche depends on the species structural adaptions, physical responses and behavior Niche overlap means that one or more resources are shared beteen two species .

Which of the following ways is most likely to decrease the genetic diversity in a population?

  1. Gene mutation

  2. Genetic recombination

  3. Stabilising natural selection

  4. Immigration of individuals


Correct Option: C
Explanation:
  • Genetic diversity is the total number of genetic characteristics in the genetic makeup of a species. For example, The genetic diversity shown by the medicinal plant Rauwolfia vomitoria growing in different Himalayan ranges might be in terms of the potency and concentration of the active chemical (reserpine) that the plant produces. 
  • Genetic variation is an important force in evolution as it allows natural selection to increase or decrease the frequency of alleles already in the population.
  • Stabilizing natural selection is most likely to decrease the genetic diversity in a population because the frequency of alleles remains constant in stabilized natural selection.
  • So, the correct answer is 'Stabilising natural selection'.

Which of the following is incorrectly matched?

  1. Alpha diversity Number of species in a given habitat

  2. Genetic diversity Variation of genes within species

  3. Beta-diversity - Diversity of habitat in the whole region

  4. Species diversity - The product of species richness and evenness


Correct Option: B
Explanation:
Genetic diversity is the total number of genetic characteristics in the genetic makeup of a species. It is distinguished from genetic variability, which describes the tendency of genetic characteristics to vary. Genetic diversity serves as a way for populations to adapt to changing environments. With more variation, it is more likely that some individuals in a population will possess variations of alleles that are suited for the environment. Those individuals are more likely to survive to produce offspring bearing that allele. The population will continue for more generations because of the success of these individuals. The academic field of population genetics includes several hypotheses and theories regarding genetic diversity. The neutral theory of evolution proposes that diversity is the result of the accumulation of neutral substitutions. Diversifying selection is the hypothesis that two subpopulations of a species live in different environments that select for different alleles at a particular locus. This may occur, for instance, if a species has a large range relative to the mobility of individuals within it. Frequency-dependent selection is the hypothesis that as alleles become more common, they become more vulnerable. This occurs in host–pathogen interactions, where a high frequency of a defensive allele among the host means that it is more likely that a pathogen will spread if it is able to overcome that allele.
So the correct option is 'genetic diversity- variation of genes within species'.

The term $\alpha$ - diversity refers to

  1. Genetic diversity

  2. Community and ecosystem diversity

  3. Diversity among the plants

  4. Species diversity


Correct Option: D
Explanation:

The local species pool is known as alpha diversity. It is also the diversity present within the community. The term was introduced by R. H. Whittaker. Example of such diversity includes high tree diversity throughout the Amazon Rainforests of Ecuador. Generally, gamma diversity = alpha diversity x beta diversity.

So, the correct answer is 'Species diversity'.

Which of the following represents the biodiversity of an area?

  1. Gene

  2. Species

  3. Ecosystem

  4. All of the above


Correct Option: B
Explanation:

In our biosphere immense diversity (or heterogeneity), exists not only at the species level but at all levels of biological organisation ranging from macromolecules within cells to biomes. Biodiversity is the term popularised by the sociobiologist Edward Wilson to describe the combined diversity at all the levels of biological organisation. The most important of them are- 
(i) Genetic diversity.
(ii) Species diversity.
(iii) Ecological diversity.

Number of known species of organisms on this earth is

  1. 5.0 million

  2. 3.2 million

  3. 1.7 million

  4. 1.32 million


Correct Option: C
Explanation:

A great biodiversity exists on our planet. Millions of living plants and animal species are flourishing on Earth. An approximate of 1.7 million organisms are known to exist. New species are getting discovered and recorded every year.

So, the correct answer is '1.7 million'.

Percentage of insect species out of the total known organisms is

  1. 75

  2. 61

  3. 53

  4. 47


Correct Option: B
Explanation:

Great biodiversity exists on our planet. Millions of living plants and animal species are flourishing on Earth. An approximate of 1.7 million organisms are known to exist. 61% of the total known species are of insects.

So, the correct answer is '61'.

Number of mammal species recorded in India is 

  1. 64

  2. 209

  3. 119

  4. 309


Correct Option: D
Explanation:

Great biodiversity exists on our planet. Millions of living plants and animal species are flourishing on Earth. An approximate of 1.7 million organisms are known to exist. Out of them, 309 mammal species are recorded in India.

So, the answer is '309'.

Largest living lemur, Indri indri occurs in

  1. India

  2. Mauritius

  3. Fiji

  4. Madagascar


Correct Option: D
Explanation:

Indri indri lemur also known as babakoto, is the largest living lemur on Earth. It as a head-and-body length of about 64–72 cm (25–28 in) and a weight of between 6 to 9.5 kg (13 to 21 lb). It occurs in Madagascar. It plays an important part in the myths of the residents of Madagascar, and legends with various stories in existence accounting for its origin. According to IUCN, it is classified as a critically endangered species.

So, the correct answer is 'Madagascar'.

Number of plant species estimated to be present in India is 

  1. 40,000

  2. 45,000

  3. 58,000

  4. 80,000


Correct Option: B
Explanation:

India is one of the richest countries when it comes to the diversity of plant species. Around 45,000 plant species are estimated to be present in India. There are eight main florist regions in India which are Western Himalayas, Eastern Himalayas, Assam, Indus plain, Ganges plain, the Deccan, Malabar, and the Andaman Islands. So, great efforts for protecting the immense biodiversity should be done.

So, the correct answer is '45,000'.

Which of the following is incorrect?

  1. Stellars Sea Cow and Passenger Pigeon got extinct due to over exploitation

  2. Lantana and Eichhornia are invasive weed species in India

  3. Species diversity increases from equator to poles

  4. Convention on biological diversity was held in 1992

  5. Among animals, insects are the most species rich taxonomic group


Correct Option: C
Explanation:

Species diversity decreases from equator to poles. The reason lies behind the fact that the conditions for the survival of species at poles become unfavorable. The Equator has favorable conditions for the survival of wildlife. Good vegetation, sunlight, and habitat these factors are responsible for great biodiversity at the equator.

So, the correct answer is 'Species diversity increases from equator to poles'.

Which one shows maximum genetic diversity in India?

  1. Groundnut

  2. Rice

  3. Maize

  4. Mango


Correct Option: D
Explanation:
Genetic diversity represents the total number of genetic characteristics in the genetic makeup of a species. Whereas, the genetic variability describes the tendency of genetic characteristics to vary. This diversity lets the population adapt to changing environments. For example, In India, we find mangoes with different flavors, colors, fiber content, sugar content, and shelf life, as it has the greatest genetic diversity in our country. The great variation is due to the genetic diversity. 
So, the correct answer is 'Mango'.

Which region is rich in species diversity?

  1. North Pole

  2. Temperate region

  3. Tropical region

  4. South Pole


Correct Option: C
Explanation:

Species diversity increases towards the equator. The two main reasons are phylogenetic niche conservatism and ecological productivity. The relatively high temperatures in the tropics generate and maintain high diversity. However, the tropical rainforests in developing countries are getting cleared nowadays, which is leading to a great loss of biodiversity.

So, the correct answer is 'Tropical region'.

Indian share in global species diversity is about

  1. 8%

  2. 6%

  3. 4%

  4. 2%


Correct Option: A
Explanation:

Great biodiversity exists on our planet. Millions of living plants and animal species are flourishing on Earth. An approximate of 1.7 million organisms are known to exist. New species are getting discovered and recorded every year. Indian share in global species diversity is about 8%.

So, the correct answer is '8%'.

Which one has the largest species variety in India?

  1. Potato

  2. Maize

  3. Wheat

  4. Rice


Correct Option: D
Explanation:

Species diversity is the number of different species that are represented in a given community. In India, rice has the largest species diversity or variety. India has 6,000 species variety of rice. The number has greatly reduced from before. The commonest rice is basmati rice.

So, the correct answer is 'Rice'.

Which of the following statements is correct?

  1. Species diversity, in general, increases from poles to the equator

  2. Conventional taxonomic methods are equally suitable for higher plants and microorganisms

  3. Indias share of global species diversity is about 18%

  4. There are about 25000 species of plants in India


Correct Option: A
Explanation:
In general, species diversity, in general, increases from poles to the equator. With very few exceptions, tropics (latitudinal range of 23.5° N to 23.5° S) harbor more species than temperate or polar areas. The reason is that tropical environments, unlike temperate ones, are less seasonal, relatively more constant and predictable. Such constant environments promote niche specialization and lead to greater species diversity.
So, the correct answer is 'Species diversity, in general, increases from poles to the equator'.

Who observed that within a region, species richness increased with increasing explored area but only upto a limit?

  1. Paul Ehrlich

  2. David Tilman

  3. Alexander von Humboldt

  4. Edward Wilson

  5. Robert Mayr


Correct Option: C
Explanation:
During his pioneering and extensive explorations in the wilderness of South American jungles, the great German naturalist and geographer Alexander von Humboldt observed that within a regional species richness increased with the increasing explored area, but only up to a limit. In fact, the relationship between species richness and area for a wide variety of taxa (angiosperm plants, birds, bats, freshwater fishes) turns out to be a rectangular hyperbola. On a logarithmic scale, the relationship is a straight line described by the equation log S = log C + Z log A where S= Species richness A= Area Z = slope of the line (regression coefficient) C = Y-intercept.
So, the correct answer is 'Alexander von Humboldt'.

India is one of the twelve megadiversity countries with ______ of genetic resources of the world.

  1. 12.1%

  2. 18.1%

  3. 38.1%

  4. 8.1%


Correct Option: D
Explanation:
Although India has only 2.4 per cent of the world’s land area. But its share of the global species diversity is an impressive 8.1 percent. That is what makes our country one of the 12 megadiversity countries of the world. Nearly 45,000 species of plants and twice as many of animals have been recorded from India. 
So, the correct answer is '8.1%'.

Black buck, golden langur and Asiatic wild ass are likely to be in danger of extinction. This species belongs to

  1. Extinct

  2. Endangered

  3. Vulnerable

  4. Rare


Correct Option: B
Explanation:

Blackbuck, Golden langur, and Asiatic wild ass are likely to be in danger of extinction and are classified as endangered (as their population is decreasing) by IUCN red data list.

So, the correct answer is 'Endangered'.

Regional diversity is also called

  1. Alpha diversity

  2. Beta diversity

  3. Gamma diversity

  4. Ecosystem diversity


Correct Option: B
Explanation:
Alpha diversity refers to the average species diversity of a habitat. Beta diversity is the diversity species between two habitats or regions and is given by the ratio between local (alpha species diversity) and regional species diversity. It is also known as the regional species diversity. Gamma diversity is the total diversity of a landscape.
So, the correct option is 'Beta diversity'.

India is among $12$ megadiversity countries of world, due its percentage contribution in global species diversity, that is:-

  1. $1.8 \%$

  2. $2.4 \%$

  3. $8.1 \%$

  4. $4.2 \%$


Correct Option: C
Explanation:

Megadiversity refers to the diversity in various life forms. India is one of the megadiverse countries where diversity of global species is found. There are 4 biodiversity hotspots (the area where large species diversity is present) in India, they are:

  1. Himalaya
  2. Indo-Burma
  3. Sundaland
  4. The Western Ghats and Sri Lanka
In India, the total area under biodiversity hotspot is about 2.4 % and its contribution to global species diversity is about 7 - 8.5 %.
So, the correct option is '8.1%'.

Which evolutionary force decreases the genetic diversity of a population by increasing the proportion of smaller individuals?

  1. Mutation

  2. Gene flow

  3. Bottle neck effect

  4. Random mating


Correct Option: C

Quinine is obtained from

  1. Leaves of Cinchona

  2. Roots of Cinchona

  3. Bark of Cinchona

  4. Seeds of Cinchona


Correct Option: C
Explanation:

Quinine occurs naturally in the bark of the Cinchona tree, though it has also been synthesized in the laboratory. The medicinal properties of the Cinchona tree were originally discovered by the Quechua, who are indigenous to Peru and Bolivia, later the Jesuits were the first to bring Cinchona to Europe.

Thus, the correct option is C.

Tendency of increase of species diversity in transition zone between two community is called as

  1. Ecotone effect

  2. Edge effect

  3. Border effect

  4. Complementary effect


Correct Option: B
Explanation:

In ecology, edge effects refer to the changes in population or community structures, that occur at the boundary of two habitats. Areas with small habitat fragments exhibit especially pronounced edge effects that may extend throughout the range. As the edge effects increase, the boundary habitat allows for greater biodiversity.

A tiger will think twice before attacking this animal, even though it is alone. Which is it ?

  1. Nilgai

  2. Wild dog

  3. Wild buffalo

  4. Chital


Correct Option: C
Explanation:

The tiger (Panthera tigris) is the largest cat species, reaching a total body length of up to 3.38 m (11.1 ft) over curves and weighing up to 388.7 kg (857 lb) in the wild. Its most recognizable feature is a pattern of dark vertical stripes on reddish-orange fur with a lighter underside. The species is classified in the genus Panthera with the lion, leopard, jaguar and snow leopard. Tigers are apex predators, primarily preying on ungulates such as deer and bovids.  The wild  buffalo (Bubalus arnee), also called Asian buffalo and Asiatic buffalo, is a large bovine native to the Indian Subcontinent and Southeast Asia.
Tigers will be mostly killed by wild buffaloes, when they both fight. So, a tiger will have to think twice before attacking wild buffalo.

Genetic diversity will be more common in organisms with 

  1. Parthenogenesis

  2. Sexual reproduction

  3. Asexual reproduction

  4. Parthenocarpy


Correct Option: B
Explanation:

Genetic diversity refers to the variety of genes within a species. Each species is made up of individuals, that have their own particular genetic composition. Within a species there may also be discrete populations with distinctive genes. 

Asexual reproduction results in no new gene configurations, so the offspring is genetically identical to the parent. 
Sexual reproduction results in an offspring, that receives genes from two parents. The advantage of sexual reproduction occurs when the two parents come from different populations. This way the genetic info is the combination of two parents from two separate populations. This is why young male lions are kicked out of the pride and why it is illegal to marry your cousin, as this insures genetic diversity.

The conservation of local (endemic) varieties of crops is must because

  1. These are source of genes for genetic diversity.

  2. These are high yielding and nutritious.

  3. We want to conserve all plants and animals of the past for our knowledge.

  4. All of the above.


Correct Option: A
Explanation:

Genetic diversity refers to the variety of genes within a species. Each species is made up of individuals that have their own particular genetic composition. Within a species there may also be discrete populations with distinctive genes. Sexual reproduction is critical for maintaining genetic diversity within a species, because it combines the parents genetic material, resulting in offspring with unique genetic blue prints different from either parent. 

The conservation of local varieties are important, as they provide genes for genetic diversity.

Greatest genetic diversity of crop plant is found in

  1. Central America

  2. Homelands

  3. South America

  4. India


Correct Option: B
Explanation:

Diversity in crops is showcased as genetic and phenotypic characters. These include variety of  the size of seeds, branching pattern, height differences, flower color, fruiting time and flavor. Genetic diversity is the total number of genetic characteristics that make up the species and play a major role in modern plant breeding and the greatest diversity in crop plants is seen in the homelands.

Species diversity in an ecosystem mainly depends on

  1. Light intensity

  2. Less temperature

  3. Rain fall

  4. Soil type


Correct Option: C
Explanation:

Species diversity is a measure of the diversity within an ecological community that incorporates both species richness (the number of species in a community) and the evenness of species abundances and it varies from region to region and mainly depends on rainfall apart from other other factors like temperature, light intensity etc. 

Therefore, the correct answer is option C.

Which one of the following shows maximum genetic diversity in India?

  1. Groundnut

  2. Rice

  3. Maize

  4. Mango


Correct Option: B
Explanation:

Rice has more than 50,000 genetically different strains, while mango has 1000 varieties in India. 

Therefore, the correct answer is option B.

Four species of birds have different egg colours: [1] white with no markings, [2] pale brown with no markings, [3] grey-brown with dark streaks and spots, [4] pale blue with dark blue-green spots. Based on egg colour, which species is most likely to nest in a deep tree hole?

  1. 1

  2. 2

  3. 3

  4. 4


Correct Option: A
Explanation:

White birds with no markings would likely to nest in a deep tree hole as they can't camouflage with the surroundings and can easily be prey for its predators. Others can hide themselves under the color of trees. 

Therefore, the correct answer is option A.

How many species are believed to exist on Earth at present time?

  1. 5,000 to 10,000.

  2. Approximately 100,000.

  3. Approximately 500,000.

  4. Between 5 million and 30 million.


Correct Option: D
Explanation:

The total variability of life forms on planet Earth is measured called as global biodiversity which is reported to be between 5 million and 30 million at present scenario.

So, the correct answer is option D.

Different local population of a species is known as 

  1. Deme

  2. Sister population

  3. Community

  4. None of the above


Correct Option: B
Explanation:

Population is a unit of biotic community made of near group of multi breeding individuals of a species found in a geographical area at a particular time. It is called as deme.
Different populations of a species occupying different geographical areas are called as sister populations. 

Therefore, the correct answer is option B.

How does the genetic diversity of a modern corn field compare to the genetic diversity of a population of the pre-domesticated corn plant?

  1. Less diversity

  2. More diversity

  3. More genetic diversity, but less phenotypic variation

  4. The same amount of diversity


Correct Option: B
Explanation:

The genetic diversity of a modern corn field is more diverse as it may contain genes transferred from from bacteria, to naturally protect it from pests 

For example, Bt corn
However, a pre domesticated corn plant is the one that is most suitable to be grown in a certain environment, majorly by artificial selection that is cross breeding and deriving a gene pool from an existing one that can provide a better commercial value
Example - sweet corn, a recessive trait, but is abundantly available due to taste preference and comparatively soft kernels

All of these are reasons why biodiversity is important except

  1. It allows for adjustment to disturbances .

  2. It cleans water.

  3. It provides food and materials.

  4. It has led to medical discoveries.

  5. It increases extinction rates.


Correct Option: E
Explanation:
A. Biodiversity allows for adjustments to various disturbances. For example, trees control the rainfall.
B. As the polluted water flows through the dense areas having plants, it gets cleaned naturally.
C. Biodiversity provides food both for animals and mankind.
D. Biodiversity has to medical discoveries as various medicinal plants have been discovered.
E. Biodiversity reduces the extinction rates.
Hence statement E is incorrect.
So, the correct answer is 'It increases extinction rates'.

All of these are human activities that threaten biodiversity except  

  1. The release of excess nitrates from agricultural runoff

  2. Over-harvesting of plants and animals

  3. Overuse of herbicides

  4. Habitat preservation

  5. Excessive ultraviolet radiation from a depleted ozone layers


Correct Option: D
Explanation:
A. Various fertilizers are used in agriculture which contain nitrogen as a key component. Runoff from agricultural land causes the release of excess nitrates.
B. Over harvesting of plants and animals for profit by the mankind has resulted into extinction of various species.
C. Overuse of herbicides kills the soil microflora and other microorganisms also.
D. Habitat preservation is not a threat to biodiversity as it will save the species.
E. Ozone has depleted due to various human activities like CFCs and due to this, excess ultraviolet rays can reach the earth and cause various problems to biodiversity.
Hence statement C is incorrect.
So, the correct answer is 'Habitat preservation'.

The greatest threat to genetic diversity in agricultural crops is

  1. Extensive use of insecticides and pesticides

  2. Extensive mixed cropping

  3. Introduction of high yielding varieties

  4. Extensive use of fertilisers


Correct Option: C
Explanation:

Genetic diversity is the diversity in the number and types of genes present in different species and variations in the genes of the same species. The greatest threat to genetic diversity in agricultural crops is introduction of high yielding varieties. High yielding varieties contains the required traits and therefore are always bred purely. This reduces the genetic diversity within a particular species.

Thus, the correct answer is 'Introduction of high yielding varieties.'

Select the incorrect statement.

  1. Species diversity increases as we move away from the equator towards the poles.

  2. Stellars sea cow and passenger pigeon got extinct due to over exploitation by man.

  3. Lantana and Eichhornia are invasive weed species in India.

  4. The historic convention on biological diversity was held in 1992.

  5. Among animals, insects are the most species-rich taxonomic group.


Correct Option: A
Explanation:

Species diversity is the variety in the number and richness of the species of a region. The number or species per unit area is called as species richness. Number of individuals of different species represent species evenness or species equitability. Communities where species are represented by more or less equal number of individuals exhibit evenness. Where one or more species have more individuals than other show dominance or unevenness. 

Tropical rain forests in the equatorial regions and coral reefs have fragile environment and vulnerable habitats. They also have the maximum biodiversity despite having little seasonal changes in the temperature and moisture. Very harsh conditions e.g., polar regions, results in reduction in biodiversity.

Which one of the following has maximum genetic diversity in India?

  1. Teak

  2. Mango

  3. Wheat

  4. Tea


Correct Option: B
Explanation:

India is one of the twelve megadiversity regions of the world with 7.7 percent of genetic resources of the world. 

Western Ghats have wild relatives of a number of cultivated plants like banana, citrus, mango, pepper etc. 
Common mango (Mangifera indica) originated as alloploid and its native home was suggested as Eastern India, Assam to Burma or possibly further in the Malay region (Popenoe, 1920). 
Vavilov (1926) also suggested Indo-Burma region as the centre of origin of mango. Hence, mango shows maximum genetic diversity in India. 

India's share in the global species diversity is about

  1. 2 percent

  2. 4 percent

  3. 6 percent

  4. 8 percent


Correct Option: D
Explanation:

Species diversity is the diversity at the species level. For example, the western Ghats have a greater amphibian species diversity than the eastern Ghats. Although India has only 2.4 per cent of the world's land area, its share of the global species diversity is an impressive 8.1 per cent. That is what makes our country one of the 12 mega diversity countries of the world.

Ecological diversity includes

  1. Species diversity

  2. Genetic diversity

  3. Ecosystem diversity

  4. All of the above


Correct Option: D
Explanation:

In our biosphere immense diversity (or heterogeneity) exists not only at the species level but at all levels of biological organisation ranging from macromolecules within cells to biomes. Biodiversity is the term popularised by the sociobiologist Edward Wilson to describe the combined diversity at all the levels of biological organisation. 

The most important of them are -
(i) Genetic diversity.
(ii) Species diversity.
(iii) Ecological diversity.

Write the correct sequence of genetic diversity.

  1. Kingdom $\rightarrow$ species $\rightarrow $chromosomes$ \rightarrow $genes $\rightarrow$ nucleotides

  2. Population $\rightarrow$species $\rightarrow$ chromosomes $\rightarrow$ genes $\rightarrow$ nucleotides.

  3. Species $\rightarrow$ genes $\rightarrow$population $\rightarrow $ chromosomes$ \rightarrow $ nucleotides

  4. Kingdom $ \rightarrow$ population $\rightarrow$ species $\rightarrow$ genes $\rightarrow$ chromosome $\rightarrow$ nucleotides


Correct Option: B
Explanation:

Genetic diversity is the diversity in the number and types of genes as well as chromosomes present in different species and variations in the gene and their alleles in the same species.
Population $\rightarrow $Species $\rightarrow $Chromosomes $\rightarrow $Genes $\rightarrow $Nucleotide is the correct sequence of genetic diversity.

Which of the following ecosystems exhibits maximum genetic variations?

  1. Tropical rain forests

  2. Tropical evergreen forests

  3. Coniferous forests

  4. Temperate forests


Correct Option: A
Explanation:

Species diversity or genetic variation increases as one proceeds from high altitude to low altitude and high latitude to low latitude. Tropical rain forests are wet and dense. They exhibit maximum genetic variations due to increased temperature and rainfall.  They show high animal and plants biodiversity. 

Thus, the correct answer is 'Tropical rain forests.'

Which of the following helps in maintaining species diversity in a community?

  1. Omnivores

  2. Predators

  3. Herbivores

  4. Facultative parasites


Correct Option: B
Explanation:

Species diversity is defined as the number of different species in a given community. The species diversity in a community is maintained by predators. Predators are organisms that feed on prey. They can increase, decrease or leave unchanged species diversity. They increase species diversity by preying on competitive dominant species and reduce species diversity by reducing consumer pressure on foundation species.

Thus, the correct answer is 'Predators.'

Let no one species encroach over the right and privileges of other species is the stanza from

  1. Atharva Veda

  2. Isha Upanishad

  3. Kautilyas Arthashastra

  4. Bhagvat Geeta


Correct Option: B
Explanation:

Isha Upanishad is one of shortest Upanishads, which is embedded as the final chapters of Shukla Yajurveda, the following stanza is found in this upanishad.

So, the correct answer is 'Isha Upanishad'

Species diversity increases as one proceeds from

  1. High altitude to low altitude and high latitude to low latitude

  2. Low altitude to high altitude and high latitude to low latitude

  3. Low altitude to high altitude and low latitude to high latitude

  4. High altitude to low altitude and low latitude to high latitude


Correct Option: A
Explanation:

  • Species diversity increases as one proceeds from high altitude to low altitude and high latitude to low latitude. The temperature and seasonal variability increases with increased altitude and decreased latitude. Hence, this results in higher species diversity in these areas.

Thus, the correct answer is 'High altitude to low altitude and high latitude to low latitude.'

Gymnosperm species known from India is

  1. 119

  2. 209

  3. 64

  4. 48


Correct Option: C
Explanation:

Gymnosperms mean naked seeds; their ovules are naked and freely exposed to pollination, and the fertilized seeds are not enclosed by carpels. Great biodiversity exists on our planet. Millions of living plants and animal species are flourishing on Earth. An approximate of 1.7 million organisms are known to exist. 64 gymnosperm species are known from India.

So, the correct answer is '64'.

A species spread over a large tract with varied environmental conditions will have

  1. Higher genetic diversity

  2. Uniform gene pool

  3. Little genetic diversity

  4. Either B or C


Correct Option: A
Explanation:

The variety and variability of living organisms (both plants and animals) are known as biodiversity. The variation measured by biodiversity is at the genetic, species, and ecosystem level. Gene-based diversity is known as genetic diversity. It is a way for populations to adapt to changing environments. A species spread over a large tract with varied environmental conditions will have higher genetic diversity.

So, the correct answer is 'Higher genetic diversity'.

In India, we find mangoes with different flavours, colours, fibre content, sugar content and shelf life. The large variation is due to 

  1. Genetic diversity

  2. Species diversity

  3. Induced mutations

  4. Hybridisation


Correct Option: A
Explanation:
Genetic diversity represents the total number of genetic characteristics in the genetic makeup of a species. Whereas, the genetic variability describes the tendency of genetic characteristics to vary. This diversity lets the population adapt to changing environments. For example, In India, we find mangoes with different flavors, colors, fiber content, sugar content and shelf life. The great variation is due to the genetic diversity.
So, the correct answer is 'Genetic diversity'.

Beta diversity is diversity

  1. In a community

  2. Between communities

  3. In mountain gradient

  4. On a plain


Correct Option: B
Explanation:

Beta diversity is the diversity present between the communities. It is also the rate of replacement of species along a gradient of habitats/communities. Whereas, the local species pool is known as alpha diversity and the diversity present in the ranges of communities is known as Gamma diversity.

In general, Gamma diversity=Alpha diversity x Beta diversity.
So, the correct answer is 'Between communities'.

The relation between species richness and area is correctly depicted by

  1. log S = log C - Z log A

  2. log S = Z log A

  3. log S = log C + Z log A

  4. log S = log C

  5. log C = log S + Z log A


Correct Option: C
Explanation:

The relationship between the area of a habitat, or of part of a habitat, and the number of species found within that area is described by the species-area curve. It says that log S = log C + Z log A. Here S is the number of species, A is the habitat area, and Z is the slope of the species-area relationship. Larger areas tend to contain larger numbers of species.
So, the correct answer is 'log S = log C + Z log A'.

Which scientist proposed alphaα types species diversity?

  1. Bentham and Huxley

  2. Linnaeus

  3. Whittaker

  4. Eichler


Correct Option: C
Explanation:

The local species pool is known as alpha diversity. It is also the diversity present within the community. The term was introduced by R. H. Whittaker. Example of such diversity includes high tree diversity throughout the Amazon Rainforests of Ecuador. Generally, gamma diversity = alpha diversity x beta diversity.

So, the correct answer is 'Whittaker'.

The number of taxa present within a particular area or an ecosystem is

  1. $\alpha$ - diversity

  2. $\beta$ - diversity

  3. Gamma diversity

  4. Delta diversity


Correct Option: A
Explanation:

The number of taxa present within a particular area or an ecosystem is called alpha diversity. It is also the diversity present within the community. The term was introduced by R. H. Whittaker. Example of such diversity includes high tree diversity throughout the Amazon Rainforests of Ecuador. Generally, gamma diversity = alpha diversity x beta diversity.

So, the correct answer is 'α - diversity'.

The species in which the evolutionary process has been influenced by man to meet his need is called.

  1. Adventives species

  2. Introduced species

  3. Naturalized species

  4. Domesticated species


Correct Option: A

Which one of the following has maximum genetic diversity in India ?

  1. Tea

  2. Teak

  3. Mango

  4. Wheat


Correct Option: D

Ten species (i) to (x) sampled in four areas  $A-D$ having $11-13$ habitats (given in brackets) possess populations (in thousands) given in the table. Which one has the maximum species diversity

(i) (ii) (iii) (iv) (v) (vi) (vii) (viii) (ix) (x)
A (11) 2.3 1.2 0.52 6.0 - 3.1 1.1 9.0 - 10.3
B (11) 10.2 - 0.62 - 1.5 3.0 - 8.2 1.1 11.2
C (13) 11.3 0.9 0.48 2.4 1.4 4.2 0.8 8.4 2.2 4.1
D (12) 3.2 10.2 11.1 4.8 0.4 3.3 0.8 7.3 11.3 2.1
  1. A

  2. B

  3. C

  4. D


Correct Option: D
Explanation:

A) The given region does not have much species richness. 

B) The given region has the least species richness. 
C) The region has the second largest (sum total) of species richness. 
D) The region has the most species richness (by adding up the columns). 
So the correct answer is 'D'. 

Select an incorrect statement about biodiversity.

  1. Mountain peaks are more diverse than foot hills.

  2. Valley's are more diverse than mountain peaks.

  3. Shade sides are more diverse than sun sides of mountains.

  4. Western ghats are more diverse than eastern ghats.


Correct Option: A
Explanation:

Valleys, shade side of mountains and western ghats have more trees and water resources where more diverse fauna and flora may be present due to the availability of their life-sustaining resources comparing with the others. Foothills, when compared with the mountain peak, are more diverse because mountain peaks are at higher altitude there is more sunlight, less water or we can say no water and also colder climate when compared to foothills so it will mostly be covered with either snow or there will exist a grassland.


So the correct option is 'A'.

What is the approximate ratio of animals and plants species in our country? 

  1. 3 : 1

  2. 2 : 1

  3. 1 : 3

  4. 1 : 2


Correct Option: B
Explanation:

India is very rich in varieties of animals and plants species. Around 47,000 species of plants and twice the number of  animals have been recorded in India. Around 81,000 species of animals have been recorded in India. Hence, the ratio of animals and plants species in India is 2:1.

Thus, the correct answer is '2:1.'

Choose the wrong statement.

  1. Species diversity increases as we move away from the equator towards the poles.

  2. Stellar's sea cow and passenger pigeon got extinct due to over exploitation by man.

  3. Lantana and Eicchornia are invasive weed species in India.

  4. The historic 'Convention on Biological Diversity' was held in 1992.

  5. Among animals insects are the most species rich taxonomic group.


Correct Option: A
Explanation:

Statement A is incorrect as species diversity decreases and not increases as we move away from the equator towards the poles temperature decreases and conditions becomes harsh, vegetation decreases and less resources available to support species. 

Statement B is correct as Stellar's sea cow and passenger pigeon had extinct which is because of over exploitation by man. 
Statement C is correct as Lantana and Eicchornia are invasive weed species in India. These weeds invades disturbed natural ecosystems and adversely affects biodiversity. The weed is distributed throughout India.
Statement D is correct as the historic 'Convention on Biological Diversity' was held in 1992, Biodiversity Convention which is a multilateral treaty. 
Statement E is correct as among animals insects are the most species rich taxonomic group, they are most abundant species among animals.
Therefore, the correct answer is option A.

"Human Genetic Diversity: Lewontin's Fallacy" is a 2003 paper by

  1. Malthus

  2. Edward

  3. Lamarck

  4. Darwin


Correct Option: B
Explanation:

"Human Genetic Diversity: Lewontin's Fallacy" is a 2003 paper by A. W. F. Edwards. He criticises an argument first made by Richard Lewontin in his 1972 article "The Apportionment of Human Diversity", which argued that division of humanity into races is taxonomically invalid. Edward's critique is discussed in a number of academic and popular science books, with varying degrees of support. 

Therefore, the correct answer is option B.

The interbreeding individuals of a species showing continuous distribution are

  1. Endemic

  2. Deme

  3. Cline

  4. Ecotones


Correct Option: B
Explanation:

In biology, a deme is a term for a local population of organisms of one species, that actively interbreed with one another and share a distinct gene pool. When demes are isolated for a very long time they can become distinct subspecies or species. The term 'deme' is mainly used in evolutionary biology and is often used as a synonym for population. In evolutionary computation a "deme" often refers to any isolated subpopulation subjected to selection as a unit rather than as individuals. 

The diversity of an ecosystem of total geographical area is called 

  1. Ecological integrity

  2. $\alpha$-diversity

  3. $\beta$- diversity

  4. $\gamma$- diversity


Correct Option: D
Explanation:

Alpha diversity : species diversity within a community or habitat, comprises two components, i.e., species richness and evenness. Sometimes dominant of one vegetation stratum may affect the diversity of the other strata. 

Beta diversity : diversity is the inter community diversity expressing the rate of species turnover per unit change in habitat. 
Gamma diversity : gamma diversity is the overall diversity at landscape level includes both and  diversities. 

Number of plant species reported in India are

  1. 45,000

  2. 410

  3. 1,250

  4. 4,780


Correct Option: A
Explanation:

The flora of India is one of the richest of the world due to a wide range of climate, topology and environments in the country. It is thought there are over 17,500 species of flowering plants in India. India covers more than 45,000 species of flora, out of which there are several species that are not found anywhere else. Since ancient times, use of plants as a source of medicines has been the inherent part of life in India. There are more than 3000 officially documented plants in India that holds great medicinal potential. India comprises seven percent of world's flora.

Cheetah populations in Africa have been increasing for the past several decades from numbers in the hundreds to numbers in the thousands.
A study was conducted in which skin tissue samples were obtained from five wild cheetahs and grafted onto five other cheetahs. An immune response regarding non-self tissue rejection was absent in the cheetahs that received the skin grafts.
Recently, a small wild population of cheetahs has become infected with a new type of infectious cancer. Scientists are concerned about the extinction of the entire species because

  1. Wild cheetah populations have lost their genetic diversity and are now equally susceptible to diseases.

  2. The immune systems of the wild cheetahs have become suppressed by stressors in their environments.

  3. Wild cheetah populations are still so small that transmission of infectious diseases will occur rapidly.

  4. Skin cancer tends to metastasize faster and be more malignant than many other forms of cancer.


Correct Option: C
Explanation:

In case the species population were large, it would not face extinction in case of the rapid spread of the infectious disease, until the remedies are put in place by the scientist  to control the disease. Small population and rapid spread are the major concerns with respect to the extinction of the species

So, the correct answer is 'Wild cheetah populations are still so small that transmission of infectious diseases will occur rapidly'

Greatest genetic diversity of plants is found in

  1. Central America

  2. Homelands

  3. South America

  4. India


Correct Option: B
Explanation:

Sexual reproduction is critical for maintaining genetic diversity within a species because it combines the parents genetic material, resulting in offspring with unique genetic blueprints different from either parent. Genetic diversity is important for two reasons. First of all, when a population of an organism contains a large gene poolthat is, if the genetic blueprints of individuals in the population vary significantly the group has a greater chance of surviving and flourishing than a population with limited genetic variability. Second, genetic diversity also reduces the incidence of unfavorable inherited traits. The home lands of our food crops are vital geographic regions where the greatest genetic diversity for each species can be found. Because in homelands there are more chances of sexual reproduction with in the species which is critical for maintaining genetic diversity. Thus, option B is correct. Greatest genetic diversity of plants is not found in Central America, India and South America. Thus, other options are wrong.

Study statements (a - d) and select the two correct statements. 
(a) A lion eating a deer and a sparrow feeding on grain are consumers.

(b) Predator starfish and Pisaster help in maintaining species diversity of some invertebrates.
(c) Predators ultimately lead to the extinction of prey species.
(d) Plant chemicals like nicotine and strychnine are produced due to metabolic disorders. 

  1. c and d

  2. a and d

  3. a and b

  4. b and c


Correct Option: C

The species diversity of plants on Earth will be

  1. 2.4%

  2. 22%

  3. 8.1%

  4. 85%

  5. 70%


Correct Option: B
Explanation:

Species diversity is the number of different species, that are represented in a given community. 

Species diversity consists of two components: species richness and species evenness. Species richness is a simple count of species, whereas species evenness quantifies how equal the abundances of the species are. More than 70% of species recorded are animals and 22% are plant species.

Discovery of new species has recently picked up due to project _________.

  1. Species 2000

  2. Global Biodiversity Information Facility

  3. Agenda 21

  4. Both A and B


Correct Option: D
Explanation:

A) Species 2000 is an autonomous federation of taxonomic database custodians which involves taxonomists in the whole world. 

B) The Global Biodiversity Information Facility is an international organization which basically focusses on making scientific data on biodiversity available on the internet.
C) Agenda 21 is an action idea of the United Nations which addresses sustainable development. 
Discovery of new species has recently picked up due to project Species and 2000 and Global Diversity Information Facility.
So, the correct answer is 'Both A and B'.

A continental population of insects has blue, red, green, and black variations. The color is controlled by the interaction of two genes, one with two alleles, the other with three alleles.
A piece of driftwood carrying two green insects and five red insects floats in the ocean for several days and washes up on a small island where the insect species did not previously live. The seven insects establish a new population on the island that increases in number significantly over several generations.
Which of the following statements correctly compares the island population with the original mainland population?

  1. Red is dominantly inherited in the island population, while on the mainland green is dominant.

  2. The island population has lower genetic diversity than the mainland population.

  3. The island population is more likely to experience competition with other insect species than the mainland population.

  4. The island population size is increasing, while the mainland population is decreasing.


Correct Option: B
Explanation:

It is given that out of blue, red, green and black variations of insects, only red and green insects established a new population on the new island. Since, these four colors are controlled by two genes, new population could have either of colour of insects. It is an example of founder effect. The island population will have lower genetic diversity than the mainland population because small populations usually have less genetic diversity than large population.

Thus, the correct answer is 'The island population has lower genetic diversity than the mainland population.'

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