Topic 1a- Mitosis and Binary fission Flashcards
1
Q
what is mitosis?
A
mitosis is when a cell reproduces itself by splitting to form two identical offspring
2
Q
what is DNA doing when a cell is not dividing?
A
it is spread out in long strings
3
Q
what must a cell do before it divides?
A
- grow and increase the amount of subcellular structures such as mitochondria and ribosomes
- copy all the DNA to form x shaped chromosomes (form the X-Men frrrr)
4
Q
what is significant about the arms of each chromosome?
A
they are exact copies of each other, ready for mitosis
5
Q
what are the stages of mitosis?
A
- chromosomes line up at the centre
- cell fibres pull them apart to opposite ends of the cell
- membranes form around each of the sets of chromosomes
- these become the nuclei of two new cells
- the cytoplasm and cell membrane finally divide
6
Q
what is binary fission
A
how prokaryotic cells replicate and then divide
7
Q
what are the stages of binary fission?
A
- circular DNA and plasmids replicate
- bacterium get bigger, circular DNA strands move to opposite poles of the cell
- cytoplasm begins to divide and new cell walls begin to form
- cytoplasm divides and two new daughter cells are formed
