Topic #1: Cell Division (Paper 1) Flashcards
Revise mitosis and meiosis
What are gametes?
Sex cells that contain 23 pairs of chromosomes eg. Sperm, egg cells.
Define haploid.
A cell/nucleus with only half the number of normal chromosomes (eg. gametes)
Define diploid.
A cell with a full set of chromosomes.
How many daughter cells are produced in mitosis?
2
How many daughter cells are produced in meiosis?
4
Are the cells produced in mitosis identical or not?
Yes they are
Are the daughter cells produced in meiosis identical?
Not they are not.
Describe the 5 stages of mitosis.
1) Chromosomes, ribosomes and mitochondria duplicate, nucleus destroyed.
2) The chromosomes line up in the centre.
3) The correct pairs of chromosomes move to opposite ends.
4) The cell divides.
5) Nuclei form in the new cells.
What is a chromatid?
A copy of a chromosome.
Define cytokinesis.
When the cell splits in two.
What is the interphase?
The active life where a cell prepares for mitosis.
What are, and what is the function of stem cells?
They are unspecialised cells that can become any cell they want in order to repair damage to the body.
How do we obtain embryonic stem cells, and why are there issues surrounding their collection?
They are extracted from fertilised eggs after IVF that are not implanted in the uterus. This causes ethical issues because some belive that a fertilised egg is still a life form and that it is effectively murder.
