AP BIOLOGY

Detailed explanation-1: -Crossovers result in recombination and the exchange of genetic material between the maternal and paternal chromosomes. As a result, offspring can have different combinations of genes than their parents.

Detailed explanation-2: -Explanation: When chromatids “cross over, ” homologous chromosomes trade pieces of genetic material, resulting in novel combinations of alleles, though the same genes are still present. Crossing over occurs during prophase I of meiosis before tetrads are aligned along the equator in metaphase I.

Detailed explanation-3: -Crossing-over increases genetic variation by creating different chromosomes in offspring in comparison with their parents. The amount of genetic variation in a population is important because natural selection is dependent upon varying alleles to increase or decrease their frequencies.

Detailed explanation-4: -How does crossing over contribute to greater genetic diversity? It creates new combinations of genes in the gametes that are not found in either parent, contributing to genetic diversity.

Detailed explanation-5: -Crossing over is important for the normal segregation of chromosomes during meiosis. Crossing over also accounts for genetic variation, because due to the swapping of genetic material during crossing over, the chromatids held together by the centromere are no longer identical.