AP BIOLOGY

Detailed explanation-1: -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-2: -During the alignment, the arms of the chromosomes can overlap and temporarily fuse, causing a crossover. 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-3: -Prophase I Figure 1: Recombination is the exchange of genetic material between homologous chromosomes.

Detailed explanation-4: -Crossing over exerts genetic recombination between chromosomes. Crossing over occurs at a point called chiasma that helps in creation between non-sister chromatids. Chiasma helps in the exchange of DNA in these chromatids to form new combinations of alleles among the offspring that are genetically recombination.