Question

Which one is CORRECT about s-phase (synthetic phase)?
I. It occurs between $G_1$ and $G_2$
II. It marks the period during which DNA replicates
III. At the end of this phase DNA is doubled but the number of chromosomes remains unchanged
IV As the DNA is doubled in this phase number of chromosomes is also doubled
V. Centrioles replicate in this phase

• A. $I,II,IV,V$ are correct
• B. $I,II,III,V$ are correct
• C. All are correct
• D. Only IV is correct

Answer 1

The correct option is B $I,II,III,V$ are correct

Statement IV is incorrect while rest are correct. Only DNA is doubled during S phase. Chromosome duplication takes place during 'M' phase of cell cycle.

So, the correct option is 'I, II, III, V are correct'.