Question

Discuss the three stages of interphase and the events which occur within each stage.

Answer 1

The three stages of interphase are G1, S and G2 phases.

Explanation:

The events that takes place before cell division is termed as interphase. It is the phase of preparing cell for division also called resting phase. Interphase of the cell is marked by DNA synthesis.

The cell cycle is basically divided into two discrete phases:

Interphase and mitosis

Interphase is further divided into 3 phases:

G1,S and G2 phases

G1 Phase or first gap phase: Cell size increases in this phase, organelles are made, enzymes for replication is synthesized, nutrients are stored and various molecular subunits synthesized as a preparatory measure for DNA replication.

S- PHASE or synthesis phase: Replication of DNA takes place in the cell nucleus, centrosome is duplicated for cell division in mitosis.

G-2 phase or second gap phase: The proteins required for cell division are synthesized, cell grows much bigger. It is an important checkpoint of cell growth. Cancer cells skip the G2 phase and gets uncontrolled division. Lysosomes and mitochondria multiply in this phase so as to divide in two cells. If repair in DNA is required it is done in this phase only.