Fixed time is required for which steps of cell cycle:
A.S phaseB. M phase
C.G1 phase
D.G2 phase
E.G0phase
The Answer is. (A) S ; (B) M ; (D) G2
The time taken for S1, G2
and M phases are similar for most cell types, occupying about 6, 4
and 2 hours respectively with variations for the rapidly dividing cells
(embryonic cells), or very slow growing cells
G2 phase is most variable
because, in this phase .cells are not committed to DNA replication, can enter
resting state or progress to next cell division.
Im mammals because of the
time required for a cell to progress of S-phase through mitosis from beggning
is typically 2-24 hours irrespective of duration of G1 phase ;almost all
the varriation in proliferating rates between cell types are attributable to
the amount of time spent in G1/G0 State.
Related MCQ’s
Cell cycle: It is
the events occuring durg th period between two rmtotic dwsions.
Phases of cell cycle: -
. G1 Phase (usually 12 hr)
: Protein and RNA content increased prepration for DNA
synthesis
. S Phase (usually 6-8 hr) :
Synthesis of DNA
-G2 Phase (usually 4-5
hr) : Cytoplasmic enlargement; preparation for cell division. DNA
repair can occur in the phase.
