AP BIOLOGY

Detailed explanation-1: -A couple of homologous chromosomes, or homologs, are a set of one maternal and one paternal chromosome that pair up with each other inside a cell during fertilization.

Detailed explanation-2: -One of these chromosomes is derived from the male parent (parental chromosome) and one from the female (maternal chromosome). The chromosomes in this pair are called homologs-there is one paternal and one maternal homolog.

Detailed explanation-3: -The correct option is A. Synapsis. Synapsis is the pairing of two homologous chromosomes that occur during meiosis.

Detailed explanation-4: -During the metaphase of meiosis, there is exchange of chromatid parts between the maternal and the paternal chromatids of a pair of homologous chromosomes during meiosis. This phenomenon is known as crossing over.