Mitosis

Question 1

Prophase

Answer 1

• Chromosomes condense
• Spindle assembly
• Centrosomes move to opposite ends of the nuclear envelope
• This identifies the poles toward which the
  chromosomes move

Question 2

Kinetochores

Answer 2

specialized structure found on each chromatid, important for chromosome movement

Question 3

Polar vs Kinetochore microtubules

Answer 3

Polar microtubules: form framework of spindle and run from one pole to another
Kinetochore microtubules: attach to kinetochores and to microtubules in opposite halves of spindle

Question 4

Prometaphase

Answer 4

• Nuclear envelope breaks down
• Most cohesin removed, except at
  centromere
• Chromosomes attach to spindle

Question 5

Metaphase

Answer 5

Chromosomes aligned on equatorial/metaphase plate

Question 6

Anaphase‐promoting complex (APC)

Answer 6

spindle assembly checkpoint occurs at end of metaphase, this is inhibited if a chromosome isn’t attached properly to spindle, when all are attached, APC is activated

Question 7

Separation of sister chromatids (Anaphase)

Answer 7

Controlled by M phase cyclin‐cdk: it activates APC, APC: activates separase, which hydrolyzes cohesin

Question 8

Anaphase

Answer 8

Daughter chromosomes start
migrating to poles

Question 9

Daughter chromosomes

Answer 9

separated chromatids
- Chromatids share a centromere
- Chromosomes have their own centromere

Question 10

Telophase

Answer 10

Daughter chromosomes reach poles
- End of telophase: nuclear envelopes and nucleoli re‐form, chromatin decondenses

Question 11

3 mechanisms to move chromosomes

Answer 11

Kinetochores have motor proteins – kinesins and cytoplasmic dynein
- Kinetochore microtubules shorten, drawing chromosomes toward poles
- Centrosomes move apart, aiding in separation

Question 12

Cytokinesis in animal cells

Answer 12

Animal cells: plasma membrane pinches between the nuclei
* Ring of microfilaments of actin and myosin forms
* Proteins interact to contract and pinch the cell in two

Question 13

Cytokinesis in plant cells

Answer 13

Vesicles from GA organelle appear along cell division plane, Vesicles fuse to form a new plasma membrane, Contents of vesicles form a cell plate – the beginning of a new cell wall

Question 14

Asexual reproduction

Answer 14

offspring identical to their single parent
- Successful in unchanging environments
Single‐celled organism reproduces
itself with each cell cycle