2.1.6 cell division, diversity, organisation Flashcards
1
Q
cell cycle 4 stages
A
G1 (growth 1)
Synthesis
G2 (growth 2)
Mitosis (cytokineses)
2
Q
what triggers going from one phase to enouther
A
cyclins
3
Q
3 parts of interphase
A
g1
s
g2
4
Q
what happes in G1
A
- growth
- PROTEIN SYNTHESIS, cells make enzymes, proteins for growth
- CHECKPOINT: dna damage etc, approve going to the next
5
Q
what happens in g2
A
- more growing
- DNA is error checked and repaired
6
Q
does the cell grow during mitosis
A
no
7
Q
in whcih part of cell cycle is there the most mRNA produced
A
- G1
- protein syntehsis and production of mRNA in transcription
8
Q
product of mitosis
A
2 genetically identical daughter cells
9
Q
4 stages of mitosis
A
Prophase
Metaphase
Anaphase
Telophase
10
Q
how many chromosomes in human nucleus
A
46 (23 pairs)
11
Q
Prophase
A
- chromosomes SUPERCOIL and become visible
- nuclear envelope disintegrate
- nucleolus disappears
- centrioles move to opposite poles
12
Q
metaphase
A
- chromosomes line up at equator of cell
- SF attach to centromeres
13
Q
anaphase
A
- sister chromatides pulled apart at centromre
- SF shorten
- separated chromatids pulled to opposite poles by microtubule spindle fibres
14
Q
telophase
A
- nuclear enevlope reforms
- SF breaks down
- new nucleoluses formed
15
Q
cytokineses
A
cytoplasm and organelles divides into 2
16
Q
structure of chromosome (post DNA rep)
A
2 identical chromatids joined together at CENTROMERE
17
Q
centrosome
A
pair of centrioles