Question

how would a population be likely to change if crossing over during meiosis did not happen?

a. the population would no longer be able to reproduce.
b. offspring would be more genetically similar to their parents.
c. offspring would have fewer chromosomes than their parents.
d. there would be much more genetic variation in the population.

Explanation:

Understand the role of crossing over

Crossing Over is a vital process during prophase I of meiosis. It involves the exchange of genetic material between homologous chromosomes.

Analyze the effect of its absence

Without Crossing Over, chromosomes do not swap segments. This prevents the creation of recombinant chromosomes, which directly reduces genetic diversity.

Evaluate the given options

• Option A is incorrect because reproduction can still occur.
• Option B is correct because less recombination means offspring inherit intact parental chromosomes, making them more genetically similar to their parents.
• Option C is incorrect because chromosome number is unaffected by crossing over.
• Option D is incorrect because genetic variation would decrease, not increase.

Answer:

• (A) The population would no longer be able to reproduce.
• (B) Offspring would be more genetically similar to their parents. (Correct answer)
• (C) Offspring would have fewer chromosomes than their parents.
• (D) There would be much more genetic variation in the population.