The Cell Cycle Flashcards
What are the three stages of the cell cycle?
Interphase, nuclear division and cytokinesis.
What stage of the cell cycle dies no division take place?
Interphase.
What stage occupies most of the cell cycle?
Interphase.
What is nuclear division?
When the nucleus divides into two (mitosis) or four (meiosis).
What stage does cytokinesis follow?
Nuclear division.
What is cytokinesis?
When the cytoplasm divides to produce two (mitosis) or four (meiosis) new cells.
What is cancer?
A group of around 200 diseases caused by a growth disorder of cells.
What is cancer a result of?
Damage to the genes that regulate mitosis and the cell cycle.
What does damage to the genes that regulate mitosis lead to?
Uncontrolled growth and division of cells.
What develops and expands in size as a consequence of uncontrollable growth and division of cells?
A group of abnormal cells called a tumour.
Where can tumours develope?
In any organ of the body.
Where are tumours most commonly found?
The lungs, prostate gland, breast and ovaries, large intestine, stomach, oesophagus, and pancreas.
When does a tumour become cancerous?
If it changes from benign to malignant.
Why do cells divide by mitosis?
For growth or repair.
What is mitosis controlled by?
Two types of gene.
What does a mutation to one of the genes that control mitosis result in?
Uncontrolled mitosis.
What are mutated cells capable of forming?
Clones of themselves forming tumours.
What is the difference between malignant and benign tumours?
Malignant tumours grow rapidly, are less compact, and are more likely to be life-threatening, while benign ones grow more slowly, are more compact, and are less likely to be life-threatening.
What does the treatment of cancer involve?
Killing dividing cells by blocking a part of the cell cycle, and hence disrupting cancer growth.
How does chemotherapy disrupt the cell cycle?
Prevents DNA from replicating, and inhibits the metaphase stage of mitosis by interfering with spindle formation.
What is a problem with chemotherapy?
It also disrupts the cell cycle of normal cells.
What is chemotherapy most effective against?
Rapidly dividing cells.
Why does chemotherapy damage cancer cells to a higher degree than normal cells?
They have a faster rate of division.
Why is hair lost during chemotherapy?
As hair-producing cells have a high rate of division which is what chemotherapy is most effective against.
