Cell Cycle And Mitosis Flashcards
3.2.2
1
Q
Define mitosis
A
Division of a eukaryotic cell into two genetically identical daughter cells
2
Q
What is the role of mitosis
A
- growth of multicellular organisms
- repair of damaged tissues
- replacement of worn out cells
- asexual reproduction
3
Q
Describe Prophase
A
- chromosomes supercoil and become visible
- nuclear membrane breaks down
- centrioles migrate to opposite poles of the cell
- spindle fibres extend from the centrioles
4
Q
Describe metaphase
A
- spindle fibres attach to the centromere of each chromosome
- chromosomes line up on the equator of the spindle
5
Q
Describe anaphase
A
- spindle fibres shorten
- centromeres divide
- sister chromatids are pulled apart to opposite poles
6
Q
Describe telophase
A
- spindle fibres break down
- nuclear membrane reforms
- chromosomes begin to uncoil becoming chromatin again
7
Q
What happens during G1
A
Growth of the cell
8
Q
What happens in S phase?
A
- DNA replication occurs
- organelles also replicate
9
Q
What happens in G2?
A
DNA is checked and mistakes are corrected
10
Q
What is a malignant tumour?
A
A tumour which can spread and affect other organs, cells break off and form secondary tumours
11
Q
What is a benign tumour?
A
A tumour/mass of cells that does not spread or affect other organs
12
Q
Why are tumours damaging?
A
- put pressure on organs
- stop organs functioning correctly
- cause blockages
13
Q
Treatments for cancer
A
Chemotherapy
- drugs disrupt stages of the cell cycle
- prevent DNA replication
- inhibit spindle formation
