Cell Division - Mitosis Flashcards
Body cells normally have [ ] of each chromosome
2 copies
What is mitosis used for?
When plants and animals want to grow or replace cells that have been damaged
Define mitosis
Mitosis is when a ell reproduces itself by splitting to form 2 identical offspring
Describe the DNA in a cell that ISN’T dividing
All spread out in long strings
Describe the process of mitosis (4)
1) The DNA is copied and forms X-shaped chromosomes.
2) The chromosomes then line up at the centre of the cell and cell fibres pull them apart. The 2 arms of each chromosome go to opposite ends of the cell
3) Membranes form around each set of chromosomes, these become the nuclei of the 2 new cells
4) The cytoplasm divides
X-shaped chromosomes: Each arm of the chromosome is an [ ] of the other
exact duplicate
What happens when a cells gets a signal to divide?
It needs to replicate its DNA - so there’s one copy for each new cell
What is the end result of mitosis?
You get 2 new cells contain exactly the same DNA - they’re identical
Some organisms [ ] by mitosis. This is an example of [ ] reproduction. The offspring have exactly the same genes as the parent - there’s no [ ]
reproduce
asexual
variation