Work through the list without notes. If you cannot do a statement, follow its link, then come back. Guide = study guide; Practice = practice questions.
Understanding
- I can name the G1, G2 and M checkpoints, say where each sits in the cycle and what each one checks. (Guide: Figure 1 and the checkpoint table; Practice Q1)
- I can list what may happen to a cell that does not pass a checkpoint: pause for repair, enter G0, or undergo apoptosis. (Guide: “Checkpoints: stop or go”; Practice Q3)
- I can explain how a cyclin switches on a CDK, and what the active complex does to target proteins. (Guide: “Two proteins, two jobs”; Practice Q2)
- I can describe apoptosis and give two of its roles in the body. (Guide: “Apoptosis: programmed cell death”)
- I can explain how mutations that overactivate “drive” proteins or disable “stop” proteins can lead to cancer. (Guide: “When control fails: cancer”; Practice Q6)
Calculation and skills
- I can read a graph of cyclin concentration, CDK amount and CDK activity, and calculate the rate at which cyclin builds up. (Guide: Figure 2, Worked example 1)
- I can calculate percentages and percentage changes from cell-cycle data and quote them as evidence. (Guide: Worked example 2; Practice Q4, Q6)
- I can use a simple model to show how the balance between division and apoptosis controls cell numbers. (Practice Q7)
Reasoning
- I can predict, link by link, the effect of a cyclin that is never made or never broken down. (Guide: Worked example 1)
- I can predict the effect of a broken M checkpoint on the chromosome numbers of daughter cells. (Practice Q5)
- I can explain why losing a DNA-damage checkpoint raises the risk of cancer, using experimental data. (Guide: Worked example 2; Practice Q3)
- I can evaluate a claim that a single mutation “causes” cancer, and explain why several failures usually act together. (Practice Q6)
All ticked? You have finished Unit 4. Move on to Topic 5.1, Meiosis, or return to the course roadmap.