2.2 Mitosis And Cancer Flashcards
What are the two phases of the cell cycle?
Interphase - DNA replicates
Mitotic phase - Cell divides
What does mitosis produce?
2 genetically identical daughter cells
What are the five stages of mitosis?
- Interphase
- Prophase
- Metaphase
-Anaphase - Telophase
What happens during interphase?
DNA replicates
What happens during prophase?
Nuclear envelope breaks down and disappears. Chromosomes are free floating in the cytoplasm. Chromosomes condense and coil to become shorter and fatter and can be seen under a light microscope. Mitotic spindle begins to form between the centrioles.
What happens during metaphase?
Chromosomes line up along the middle of the cell. Spindle attaches to chromosomes at the centromere
What happens during anaphase?
Sister chromatids are separated at the centromere by spindle fibres. The chromatids are pulled to either pole of the cell.
What happens during telophase/cytokinesis?
The chromatids reach the opposite poles and begin to decondense (unravel), becoming chromosomes again.
Nuclear envelopes form around the chromosomes so there are now two nuclei.
The cytoplasm splits and two daughter cells are formed. The daughter cells are identical to the original cell and to each other.
What is a mutation?
Changes to the DNA nucleotide sequence
What is a tumour?
Group of abnormal cells formed by uncontrolled cell growth.
What do treatments against cancer target?
Disrupt the cell cycle by:
- Preventing DNA from replicating
- inhibiting metaphase by interfering with spindle formation
