What phase of cell cycle where DNA replication occurs?
The Correct Answer and Explanation is:
DNA replication occurs during the S phase (Synthesis phase) of the cell cycle.
The cell cycle consists of several stages, which include interphase (G1, S, and G2 phases) and mitotic (M) phase. Interphase is the phase where the cell prepares for division, and it accounts for the majority of the cell cycle.
During S phase, the cell’s DNA is replicated to ensure that each daughter cell will receive an identical copy of the genetic material. DNA replication is a complex process involving unwinding the double helix, separating the strands, and synthesizing complementary strands to form two identical DNA molecules.
The process begins when the enzyme helicase unwinds the double-stranded DNA, and DNA polymerase synthesizes the new complementary strands by adding nucleotides. Each original strand serves as a template for the synthesis of a new strand. The end result is two identical copies of the cell’s genome.
The G1 phase (Gap 1) occurs before the S phase, and during this phase, the cell grows and carries out normal functions. After the S phase, the cell enters the G2 phase (Gap 2), during which the cell prepares for mitosis by synthesizing proteins and organelles that will be needed for cell division.
Following interphase, the cell enters the M phase (Mitosis), where the replicated DNA is evenly divided into two daughter cells, and cell division takes place.
In summary, DNA replication specifically occurs in the S phase of the cell cycle, ensuring that the genetic material is accurately copied before cell division. This step is crucial for maintaining genetic consistency across cell generations.
