Which of the following types of natural selection reduces variation but does not change the mean value?

1.directional2.stabilizing
3.disruptive4.all of these

Subtopic:  Natural Selection |
 72%
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In modern terms, selection refers to :
1. inheritance of dominant characters
2. differential reproduction
3. a decrease in allele frequency in a population
4. differences in the contribution of various genotypes to the next generation

Subtopic:  Darwin's Theory |
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An island population faced a natural calamity and the population crashed to only 30 organisms. After some time the number of organisms grew to 5000 but still the threat of extinction is large. This is most likely due to:

1.Founder effect2.Bottleneck effect
3.Edge effect4.Heterosis

Subtopic:  Difference Between Drift & Selection |
 75%

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The number of individuals expressing the dominant phenotype in a population of 200 is 182. What is the frequency of the dominant allele in this population?

1.9 %2.30 %
3.91 %4.70 %

Subtopic:  Hardy Weinberg Law: 1 | Hardy Weinberg Law: 2 |
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Humans appeared during the epoch:
1. Pleistocene
2. Pliocene
3. Miocene
4. Oligocene

Subtopic:  Evolution of Homo Sapiens |
 57%
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A mutation appears in a sub-population of organisms separated from the other group by in the same large geographical area. This mutation can spread to the other subgroup by:
1. induced muations
2. mutations in the gene pool of the other subgroup
3. mutation pressures
4. crossovers

Subtopic:  Sources of Variation |

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Though we cannot be certain, what can be the probable reason/s for the sudden disappearance of dinosaurs from the Earth? 

I:  Climatic changes killed them
II:  Most of them evolved into birds

1.I only2.II only
3.Both I and II4.Neither I nor II

Subtopic:   A BRIEF ACCOUNT OF EVOLUTION |
 82%
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Which of the following pairs of organs do not represent analogous organs?

1. Eye of an octopus and the eye of a mammal
2. Flippers of penguins and flippers of dolphin
3. Wings of bats and forelimbs of humans
4. Wings of birds and wings of butterfly
Subtopic:  Concept of Organic Evolution: Evidence |
 85%
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Darwin got the idea of ‘common descent with modification’ as evolution initially from his observations on:
1. geographic distribution of species
2. fossil records
3. comparative embryology
4. comparative biochemistry

Subtopic:  Darwin's Theory | Summary of Darwin's Theory | Additional Theories of Darwin |
 79%

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Dinosaurs became extinct during the geological period:
1. Carboniferous
2. Jurassic
3. Cretaceous
4. Tertiary

Subtopic:   A BRIEF ACCOUNT OF EVOLUTION |
 52%
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