The 'Bottleneck effect' in population genetics refers to: MCQ with Answer and Explanation

The 'Bottleneck effect' in population genetics refers to:
A. A sharp reduction in the size of a population due to environmental events, leading to a loss of genetic variation
B. The gradual accumulation of beneficial mutations in a population
C. The non-random mating of individuals based on specific traits
D. The movement of individuals into a new population, introducing new alleles
Answer: Option A
Solution (By JKExamLibrary)
The bottleneck effect is a form of genetic drift that occurs when a population's size is drastically reduced for at least one generation due to a severe environmental event (like a natural disaster, disease, or overhunting). The surviving population is a random, small sample of the original, and its gene pool may not represent the original population's genetic diversity. This leads to a significant loss of genetic variation, making the population more vulnerable to future changes.

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Which of the following microorganisms is used in the production of bread?
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Correct Answer: Option B


Explanation:
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The enzyme that catalyzes the conversion of ATP to cAMP is:
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Correct Answer: Option A


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The condition in which the blood has a lower than normal number of red blood cells or hemoglobin is:
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Correct Answer: Option D


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