AP BIOLOGY

Detailed explanation-1: -Because of recombination and independent assortment in meiosis, each gamete contains a different set of DNA. This produces a unique combination of genes in the resulting zygote. Recombination or crossing over occurs during prophase I.

Detailed explanation-2: -Crossing over is a cellular process that happens during meiosis when chromosomes of the same type are lined up. When two chromosomes-one from the mother and one from the father-line up, parts of the chromosome can be switched. The two chromosomes contain the same genes, but may have different forms of the genes.

Detailed explanation-3: -Genetic recombination (genetic reshuffling) is the exchange of genetic material between different organisms which leads to production of offspring with combinations of traits that differ from those found in either parent. The process occurs naturally and can also be carried out in the lab.

Detailed explanation-4: -Crossing over occurs only during prophase I. The complex that temporarily forms between homologous chromosomes is only present in prophase I, making this the only opportunity the cell has to move DNA segments between the homologous pair.

Detailed explanation-5: -Meiosis also produces genetic variation by way of the process of recombination. Later, this variation is increased even further when two gametes unite during fertilization, thereby creating offspring with unique combinations of DNA.