The Cell Cycle
Cells grow, copy DNA and divide in a regulated cycle.
About this topic
The cell cycle is the ordered series of events by which a cell grows and divides. Interphase (G1, S and G2) takes most of the time: the cell grows, DNA is replicated in S phase, and it prepares for division. Then mitosis and cytokinesis form two daughter cells.
Checkpoints regulated by cyclins and enzymes check for DNA damage and proper completion. When control fails, cells divide uncontrollably, as in cancer. Some cells, like neurons, leave the cycle and stop dividing.
Skin cells divide every few weeks to replace those lost, while mature nerve cells hardly divide at all, resting in a state called G0. Before dividing, cells pass checkpoints that check for DNA damage and proper chromosome attachment; if something is wrong, the cycle halts or the cell self-destructs. Cytokinesis then splits the cytoplasm into two.
Cancer arises when mutations disable these controls, and the cells divide uncontrollably to form tumours. Many chemotherapy drugs target dividing cells, which is why they also affect hair follicles and the gut lining, causing side effects. Students often think interphase is a resting stage, but this is actually the busiest period: the cell grows and copies all of its DNA.
Key ideas
- Interphase: G1, S, G2
- Mitosis then cytokinesis
- Checkpoints prevent errors
Quick check
Use cases: where The Cell Cycle helps
- Homework: review the key idea behind The Cell Cycle before you start a problem set.
- Exam revision: use the quick check to test whether you can recall The Cell Cycle without notes.
- Visual learning: play with the interactive lab to see how The Cell Cycle changes when you adjust its inputs.
- Teaching a friend: explain The Cell Cycle in your own words, then compare your version with the key ideas.
Biology underpins medicine, farming, conservation and biotechnology.
Frequently asked questions
What is The Cell Cycle?
Cells grow, copy DNA and divide in a regulated cycle.
What will I learn in The Cell Cycle?
Interphase: G1, S, G2. Mitosis then cytokinesis. Checkpoints prevent errors.
Is The Cell Cycle part of Biology?
Yes. It is one of 150 Biology topics on LearnViz HighSchoolEdu, with 3 key ideas, a live animation and a quick check.
Does the The Cell Cycle lab work on a phone or tablet?
Yes. The animation resizes to fit your screen and supports touch, so you can drag, tap and slide with your finger.
How should I study The Cell Cycle?
Read the summary and key ideas first, play with the interactive lab to see the idea in motion, then answer the quick check. If you get a question wrong, go back to the key idea it tests.
Do I need an account, and is my progress saved?
No account is needed. Marking a topic as learned is saved in your own browser, so it stays on that device and is not sent to a server.