What is the importance of crossing over during meiosis?

• A. It increases genetic variation by exchanging DNA between homologous chromosomes.
• B. It prevents mutations from occurring during cell division.
• C. It ensures that each daughter cell receives an identical set of chromosomes.
• D. It reduces the number of chromosomes in the daughter cells.

Answer: (A)

Verified step by step guidance

1. Understand that meiosis is a type of cell division that reduces the chromosome number by half, creating four haploid cells, each genetically distinct from the parent cell.
2. Recognize that crossing over occurs during prophase I of meiosis, where homologous chromosomes pair up and exchange segments of genetic material.
3. Identify that the primary importance of crossing over is to increase genetic variation by allowing the exchange of DNA between homologous chromosomes, leading to new combinations of alleles.
4. Consider that increased genetic variation is crucial for evolution and adaptation, as it provides a population with a wider range of traits that may be beneficial in changing environments.
5. Note that while crossing over contributes to genetic diversity, it does not prevent mutations, ensure identical chromosome sets in daughter cells, or directly reduce chromosome numbers; these are functions of other processes in meiosis.