AP BIOLOGY

Detailed explanation-1: -Synthesis phase or S-phase of interphase is the phase in the cell cycle during which DNA is replicated. Each chromosome consists of two sister DNA molecules having a duplicate set of genes but the cells retain the original diploid 2n number of chromosomes.

Detailed explanation-2: -Answer : DNA replication. Explanation : S-Phase or the synthesis phase is the second phase of Interphase during cell division. It is recognized by the process of DNA duplication in which the DNA synthesis takes place in this phase.

Detailed explanation-3: -S phase is the period of wholesale DNA synthesis during which the cell replicates its genetic content; a normal diploid somatic cell with a 2N complement of DNA at the beginning of S phase acquires a 4N complement of DNA at its end.

Detailed explanation-4: -In the eukaryotic cell cycle, chromosome duplication occurs during “S phase” (the phase of DNA synthesis) and chromosome segregation occurs during “M phase” (the mitosis phase).

Detailed explanation-5: -Initiation and completion of DNA replication defines the beginning and ending of S phase of the cell cycle. Successful progression through S phase requires that replication be properly regulated and monitored to ensure that the entire genome is duplicated exactly once, without errors, in a timely fashion.