Question

Checkpoints are pauses between phases of the cell cycle during which a cell determines whether or not it is ready to proceed to the next phase. For example, because a cell with damaged DNA can lead to cancer if it is allowed to divide, it usually arrests the cell cycle until the damage can be repaired. At which phase(s) of the cell cycle would a cell normally check for the integrity of its DNA? See Section 2.3 (Page 17) View Available Hint(s) HintI DNA is usually inspected for damage prior to replication, and for the presence of sister chromatids after replication is complete. GI/S and G2/M phases M phase G2/5phase only Gsnly hase onl

Answer 1

Answer

A) G1/S and G2/M phases

Explanation :

Cell cylce involve 2 large stages

One is growing stage

Second is dividing stage

Growing stage is called Interphase

It involves 3 phases

1) G1 phase: materials required for DNA synthesis are formed during this phase

2)S phase : in this phase synthesis of DNA occurs

3)G2 phase : materials and enzymes required in dividing phase are formed during this phase

Between G1 and S phase, first check point is present which check whether tha cell is compatible for cell division or not. If any defect in DNA are present then the cell is arrested at this check point before the DNA could undergo duplication in S Phase.

Between G2 an M phase Second check point is present which check that whether the newly formed DNA and chromatids are accurate or not. If there is presence of any abnormality seen the cell is arrested before it could undergo division