Question

The protein known as p53, the product of a tumor suppressor gene, inhibits the unregulated cell division characteristic of cancers by:

a) Promoting cell division
b) Inhibiting apoptosis
c) Stimulating mutation
d) Halting the cell cycle

Answer 1

The p53 protein, produced by a tumor suppressor gene, inhibits unregulated cell division by halting the cell cycle to allow for DNA repair or initiating apoptosis if the damage is irreparable.

Step-by-step explanation:

The protein known as p53, which is the product of a tumor suppressor gene, plays a critical role in inhibiting the unregulated cell division that is characteristic of cancers. Specifically, p53 halts the cell cycle when DNA damage is detected to allow for repair before the cell can continue dividing.

If the damage is irreparable, p53 can also initiate apoptosis, or programmed cell death, preventing the propagation of mutated cells. Mutations in the p53 gene are prevalent in many types of cancer because when p53 is dysfunctional, it cannot effectively act as a guardian against the proliferation of cells with damaged DNA.