SME
Grade 9 Science
The cell cycle and its control, cancer, mitosis and meiosis
The main lesson, then each kind of problem it solves.
The cell cycle and its control, cancer, mitosis and meiosis
Main lesson
Mitotic index
Use this for “20 of 100 root-tip cells are in mitosis. How long does mitosis last in a 24-hour cycle?”
Counting chromosomes
Use this for “A body cell has 46 chromosomes. How many are in a gamete, and in a zygote?”
The cell cycle and how long each phase takes
Use this for “In which phase of the cell cycle is DNA replicated?”
Meiosis I and II
Use this for “What are the final products of meiosis?”
Mitosis, meiosis or both?
Use this for “Why do offspring from sexual reproduction vary more than those from mitosis?”
Which checkpoint stops it?
Use this for “A cell’s DNA is damaged before it is copied. Where in the cycle is it stopped?”
Normal cell or cancer cell?
Use this for “How does a cancer cell differ from a normal body cell?”