AP BIOLOGY

Detailed explanation-1: -Synapsis is the pairing of two homologous chromosomes that occurs during meiosis. It allows matching-up of homologous pairs prior to their segregation, and possible chromosomal crossover between them. Synapsis takes place during prophase I of meiosis.

Detailed explanation-2: -The tight pairing of the homologous chromosomes is called synapsis. In synapsis, the genes on the chromatids of the homologous chromosomes are aligned with each other. The synaptonemal complex also supports the exchange of chromosomal segments between non-sister homologous chromatids in a process called crossing over.

Detailed explanation-3: -This process is known as synapsis. Synapsis is when crossing over occurs. During crossing over, DNA is exchanged between two nonsister chromatids of a homologous pair of chromosomes.

Detailed explanation-4: -In prophase I of meiosis I, homologous chromosomes pair up and crossing-over occurs during this phase. In prophase II of meiosis II, homologous chromosomes do not form pairs in this way. In metaphase I of meiosis I, spindle fibers attach to the paired homologous chromosomes.