Topic 1.6: Cells
1. The cell cycle includes 4 phases: G1, S, G2, and M.
2. Interphase of the cell cycle includes G1, S, and G2.
3. Interphase is the phase in which the cell is carrying out its appointed activity or
activities. Metabolic activities such as protein synthesis, DNA replication and organelle
reproduction occur in this phase.
4. It is essential to know the important events of these phases of mitosis.
5. During prophase and metaphase the chromosome is actually two molecules of DNA
attached together at the centromere. Each molecule of DNA is called a chromatid.
6. When the chromatids of the chromosomes split during anaphase, two separate
chromosomes appear and the term chromatid is not used anymore.
7. The kinetochore of the centromere allows attachment to the spindle microtubules.
8. The microtubules are made of a protein called tubulin.
9. Mitosis produces two genetically identical nuclei.
10. Cytokinesis occurs after mitosis and is different in plant and animal cells.
11. The cytoplasm splitting which occurs during cytokinesis does not result in identical
halves. One half may have more organelles of a particular type than the other.
12. Growth, embryonic development, tissue repair and asexual reproduction involve
mitosis.
13. Chromosomes form by super coiling during mitosis.
14. Cyclins are involved in the control of the cell cycle.
15. Tumours (cancers) are the result of uncontrolled cell division and they may occur in
any organ or tissue.
16. Mutagens, oncogenes and metastasis are involved in the development of primary and
secondary tumours.
Complete the following.
1. Draw, label & annotate all the stages of mitosis.
2. Draw, label and annotate the stages of the cell cycle.
3. Determine the mitotic index from a micrograph.
4. Identify stages of mitosis in slides.
5. Describe the process of cytokinesis in plant and animal cells.
6. Discuss the involvement of cyclins in the cell cycle.
7. Contrast benign and malignant tumors.
8. Discuss mutations and how they can lead to the development of cancer.