NEET BIOLOGY

Detailed explanation-1: -During S phase, replication increases the DNA content of the cell from 2n to 4n, so cells in S have DNA contents ranging from 2n to 4n. DNA content then remains at 4n for cells in G2 and M, decreasing to 2n after cytokinesis.

Detailed explanation-2: -The S phase of a cell cycle occurs during interphase, before mitosis or meiosis, and is responsible for the synthesis or replication of DNA. In this way, the genetic material of a cell is doubled before it enters mitosis or meiosis, allowing there to be enough DNA to be split into daughter cells.

Detailed explanation-3: -S phase. In S phase, the cell synthesizes a complete copy of the DNA in its nucleus. It also duplicates a microtubule-organizing structure called the centrosome. The centrosomes help separate DNA during M phase.

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: -Because DNA is duplicated during interphase before the cell undergoes mitosis, the amount of DNA in the original parent cell and the daughter cells are exactly the same. Both genetics, as well as external factors, can play a role in the development of cancer.