AP Biology 4.6 A Describe the Role of Checkpoints in Regulating the Cell Cycle Questions
Practise AP Biology 4.6.A questions by explaining how checkpoints, cyclin-CDK interactions and p53 regulate progression after DNA damage.
Syllabus
Effective Fall 2025
Course
AP Biology
Exam points
explain how checkpoints and cyclin-CDK interactions regulate cell-cycle progression
predict cell-cycle effects of DNA damage, checkpoint failure or checkpoint mutations
connect p53 and CDK inhibitors to pausing, repair or entry into mitosis
AP Biology 4.6 A Describe the Role of Checkpoints in Regulating the Cell Cycle Questions question 1
[Maximum number: 1]
The p53 protein is a transcription factor that regulates a cell's progression through the cell cycle after DNA is damaged by ultraviolet (UV) radiation. The p53 pathway is shown in Figure 1.
Figure 1. The role of p53 in regulating cell cycle progression in response to DNA damage
Based on Figure 1, explain how p53 regulates the cell cycle in the presence of damaged DNA.
- p53 stimulates expression of the CDK inhibitor, preventing progression of the cell cycle. (The CDK inhibitor blocks the interaction between the CDK and cyclins.)