Question

The graphic represents the different stages of the cell cycle. Specific genes within the DNA, called inhibitors, stop the cell cycle in G1 phase. This process helps to keep the DNA unaltered and the cells dividing at the correct rate. Certain chemicals in our environment may result in mutations of cells' DNA that in turn prevent the inhibitors from halting the cell cycle.
If this happens, _______ may result.
A) cancer
B) cell death
C) color blindness
D) birth defects

Answer 1

Cancer or cell death could happen I got it right in my test

Answer 2

Answer:

A) cancer

Explanation:

When a cell is dividing, at that time DNA duplicates so that one copy may remain with the mother cell while another copy may be donated to the daughter cell. But before duplication, the DNA in the cell is supposed to be normal i.e. it must not have any damage. In case of any DNA damage, first our body ensures that it is properly repaired then only it can be replicated during S phase. In order to repair it, the cell cycle needs to be halted because repair requires time.

Some inhibitors like P21 proteins, ATM proteins inhibit the cell cycle during G₁ phase so that any DNA damage could be repaired. But in case these inhibitors will be prevented from halting the cell cycle, the damaged DNA will not be repaired and all the cells which will be generated from such cell will have damaged DNA or mutated DNA which will lead to cancer.