8b. Mitosis and cancer

Cards (18)

What is the diploid number of humans
46
What is a centromere
Hold the two sister chromatids together
What is a similarity between a pair of homologous chromosomes
Same genes in the same positions
What is a difference between the homologous chromosomes
Different alleles of the gene
What is mitosis used for
Increases number of cells for growth
replaces tissue during repair
asexual reproduction
What are the stages of mitosis
Interphase
prophase
metaphase
anaphase
telophase
What is interphase
No dividing - all organelle doubles
What is prophase
Chromosomes cool and condense becoming visible
What happens in metaphase
The chromosomes line up along the equator of the cell and spindle fibres attach the centromere
What happens in anaphase
Spindle fibres contract so break centromere
What happens in telophase
New nuclear membrane is formed
What is mitotic index
Tells us the number of cells dividing
How to calculate mitotic index
Cells undergoing mitosis / total cells
How do prokaryotic cells divide
Binary fission
replication of DNA, cell membrane pinches inward creating two cells.
How do viruses replicate
Injecting nucleic acid into the host cell. Used to produce viral proteins
What is cancer
Rapid uncontrolled cell division
How might protein p53 cause cancer
If it is faulty it doesn’t prevent damaged cells from dividing so cancer develops
How might cancer be treated
Preventing new cells dividing
preventing spindle fibres from forming