5. The mitotic cell cycle

5.1 Replication and division of nuclei and cells

Learning outcomes:

1. describe the structure of a chromosome, limited to:

• DNA

• histone proteins

• sister chromatids

• centromere

• telomeres

2. explain the importance of mitosis in the production of genetically identical daughter cells during:

• growth of multicellular organisms

• replacement of damaged or dead cells

• repair of tissues by cell replacement

• asexual reproduction

3. outline the mitotic cell cycle, including:

• interphase (growth in G1 and G2 phases and DNA replication in S phase)

• mitosis

• cytokinesis

4. outline the role of telomeres in preventing the loss of genes from the ends of chromosomes during DNA replication

5. outline the role of stem cells in cell replacement and tissue repair by mitosis

6. explain how uncontrolled cell division can result in the formation of a tumour

5.2 Chromosome behaviour in mitosis

Learning outcomes:

1. describe the behaviour of chromosomes in plant and animal cells during the mitotic cell cycle and the associated behaviour of the nuclear envelope, the cell surface membrane and the spindle (names of the main stages of mitosis are expected: prophase, metaphase, anaphase and telophase)

2. interpret photomicrographs, diagrams and microscope slides of cells in different stages of the mitotic cell cycle and identify the main stages of mitosis