Question 12
Which of the phases of cell cycle is of longest duration?
Interphase is of the longest duration. It has following events and is divided in the follower phases
(a) G1 phase (Gap 1) Corresponds to the interval between mitosis and initiation of DNA replication. Cell is metabolically active and continuously grows but does not replicate its DNA.
(b) S-phase (Synthesis phase) Marks the period during which DNA synthesis or replication takes place.
(i) Amount of DNA per cell doubles.
(ii) No increase in chromosome number.
(c) G2 Phase (Gap 2) Proteins are synthesised for the preparation of cell division, while cell growth continues.