A eukaryotic organism has a mutation that causes it to produce more p21 protein.Which is the most likely result of the mutation?
A) If the organism receives radiation, cell division will be slowed more than it would in an organism with normal levels of p21.
B) Cells with radiation-induced DNA damage will continue through the cell cycle without repairing the damaged DNA.
C) Cells with incomplete DNA replication will continue through the checkpoint.
D) Cells will not respond to growth factors.
E) Cells will respond too readily to growth factors.

Question

Quizplus · Accepted Answer

The p21 protein is a cyclin-dependent kinase inhibitor that can slow down the cell cycle by binding and inhibiting the activity of cyclin-dependent kinases. Therefore, an increase in p21 levels would result in increased inhibition of the cell cycle. In the presence of radiation-induced DNA damage, cells would be more likely to activate the checkpoint and slow down cell division, leading to slower progression through the cell cycle.

A Eukaryotic Organism Has a Mutation That Causes It to Produce