A cell with a defective p53 gene is likely to?

Undergo uncontrolled cell division and potentially develop into cancer.

An explanation of the answer:

Cells have internal control mechanisms designed to regulate the cell cycle and prevent unchecked cell division. The p53 protein, often referred to as the 'guardian of the genome,' plays a critical role in cell cycle regulation, DNA repair, and inducing apoptosis (programmed cell death) in damaged or stressed cells. When cellular processes detect DNA damage, the p53 protein signals a pause in the cell cycle to allow for repair. If repair is unsuccessful or is beyond a certain threshold, p53 can initiate apoptosis to eliminate damaged cells, thereby preventing mutations and the potential development of cancerous cells. However, a non-functional or mutated p53 gene will disrupt these critical mechanisms, rendering the cell susceptible to uncontrolled growth and tumor formation. Thus, defects in the p53 gene are frequently associated with an increased risk of various types of cancer.