1
Q
how to work out total magnification
A
eye piece lens x objective lens
2
Q
1 graticule divison
A
no of um / no of graticule divisions
3
Q
measuremnt in um
A
graticule divisions x magnification factor
4
Q
magnification
A
scale factor length / scale factor
5
Q
mitotic index
A
number of cells in mitosis / total cells x100
6
Q
interphase
A
- organelles multiply
- chromosomes are copied
7
Q
prophase
A
- chromosomes condense
- nulceur membrane breaks down
- centrioles move to the poles and spindle fibres start to form
8
Q
metaphase
A
- chromosomes line up at the equator of the cell
- chromosomes attach to spindle fibres via the centromere
9
Q
anaphase
A
- spindle fibres shorten and separate sister chromatids
- each chromosomes moves to an opposite pole of the cell
10
Q
telophase
A
- chromosomes reach the poles of the cell and decnodense
- nucleur membrane begins to reform
- spindle fibres break down
11
Q
cytokinesis
A
- cytoplasm & cell membrane divide
- two genetically identical daughter cells are formed
12
Q
g1 phase
A
-cell growth
- new organelles formed
- proteins synthesised
13
Q
s phase
A
dna synthesis
- dna replicated so the amount of dna doubles
14
Q
g2
A
proteins synthesized
15
Q
why does it have to be a cold isotonic buffer solution
A
- reduce activity of enzymes which may break down organelles
- prevent organelles bursting due to osmotic loss
- constant pH to avoid damage to organelles
