AP BIOLOGY

Detailed explanation-1: -Synthetic phase or S-phase of interphase, is the stage of cell cycle where DNA synthesis or replication takes place.

Detailed explanation-2: -The cell grows at a steady rate throughout interphase, with most dividing cells doubling in size between one mitosis and the next. In contrast, DNA is synthesized during only a portion of interphase.

Detailed explanation-3: -(a) DNA synthesis starts at a specific place on a chromosome called an origin. In the first mechanism one daughter strand is initiated at an origin on one parental strand and the second is initiated at another origin on the opposite parental strand. Thus only one strand grows from each origin.

Detailed explanation-4: -Interphase is composed of G1 phase (cell growth), followed by S phase (DNA synthesis), followed by G2 phase (cell growth).

Detailed explanation-5: -G1 phase together with the S phase and G2 phase comprise the long growth period of the cell cycle cell division called interphase that takes place before cell division in mitosis (M phase). During G1 phase, the cell grows in size and synthesizes mRNA and protein that are required for DNA synthesis.