W5 Cell Cycle and Division

Question 1

what happens in prophase

Answer 1

• formation of centrosomes
• chromosomes condense
• mitotic spindles form

Question 2

what are centromeres made of

Answer 2

centrioles + micro tubules

Question 3

what happens in prometaphase

Answer 3

chromosomes attach to spindle micro tubules

Question 4

how do chromosomes attach to spindle micro tubules

Answer 4

kinetochores

Question 5

what is karyotyping

Answer 5

metaphase

Question 6

what happens during metaphase

Answer 6

• chromosomes align at equator of spindle poles
• kinetochore micro tubules attach chromatids to opposite spindle poles

Question 7

what happens during Anaphase

Answer 7

• pulls sister chromatids to spindle poles
• shortens micro tubules

Question 8

why do kinetochore microtubules shorten?

Answer 8

spindle poles move apart

Question 9

what happens during telophase

Answer 9

• chromosomes move to spindle poles to decondese
• nuclear envelope reforms

Question 10

what is the end result of Mitosis

Answer 10

forms two identical daughter nuclei

Question 11

what is binary fission and how does it work

Answer 11

• unicellular mitosis
• cell elongation and DNA rep
• cross wall formation
• clone cells

Question 12

what are CDC mutants

Answer 12

• cell division cycle genes
• temperature sensitive

Question 13

what happens if CDC are mutated

Answer 13

cell cycle arrest

Question 14

what is cyclin

Answer 14

regulates cell cycle

Question 15

how is CDK complex formed

Answer 15

cyclin + inactive CDK

Question 16

whats the role of thymosin

Answer 16

binds to actin to prevent actin filaments

Question 17

whats the role of profilin

Answer 17

speeds up the binding of actin

Question 18

whats the role of formins

Answer 18

promote the filament elongation

Question 19

what are the role of integrin receptors

Answer 19

link cells to extracellular matrix

Question 20

whats the role of cadherins

Answer 20

link cells to other cells

Question 21

what are adheren junctions

Answer 21

links to F-actin filaments

Question 22

is mitosis diploid or haploid

Answer 22

diploid

Question 23

what does diploid mean

Answer 23

2 genetically identical daughter cells

Question 24

what happens in G1 phase

Answer 24

check and repair DNA
synthesise RNA + proteins
increase cell size

Question 25

what happens in G0 phase

Answer 25

resting

Question 26

what happens in S phase

Answer 26

chromosome and centrosome dupe

Question 27

what is the roles of cohesins

Answer 27

hold sister chromatids together DNA repair and gene expression

Question 28

what shape do cohesins form

Answer 28

ring structure

Question 29

what does cohesin do when metaphase anaphase transition

Answer 29

cleavage of sister chromatids

Question 30

what enzyme removes cohesin complexes

Answer 30

seperase enzyme

Question 31

what's the role of G2 phase

Answer 31

prepare for mitosis microtubule synthesis

Question 32

what's the role of M phase

Answer 32

divide + nucleus + cytoplasm condense chromosome and spindle form

Question 33

what happens when M phase and G1 fuses

Answer 33

immediately enters mitosis

Question 34

what are the role of CDKs

Answer 34

bind to cyclins to regulate cell cycle

Question 35

what are CDKS and cyclins degraded by

Answer 35

APC

Question 36

what does p53 do when switched on

Answer 36

stops cell division

Question 37

how is p53 pathway activated

Answer 37

UV light or ionizing radiation causing DNA damage

Question 38

what's the role of MPF

Answer 38

stimulate transition of G2 to M phase

Question 39

why are cyclins and CDKs degraded

Answer 39

to move out of M phase

Question 40

what can prevent phase transitions

Answer 40

DNA damage

Question 41

why is metaphase anaphase transition blocked by chromosomes

Answer 41

chromosomes still attached to spindles fibres

Question 42

what type of cells are in meiosis

Answer 42

haploid cells

Question 43

what type of cells are haploid

Answer 43

gametes

Question 44

what is formed when a egg and sperm meet

Answer 44

zygote

Question 45

when does crossing over happen in meiosis

Answer 45

during meiosis 1

Question 46

what's the point of crossing over

Answer 46

new allele combinations

Question 47

what is non disjunction

Answer 47

sister chromatids don't separate properly

Question 48

which cell cycle do budding yeast go through

Answer 48

bacteria cell cycle not human

Question 49

which CDK binds to cyclin C

Answer 49

3

Question 50

which CDK binds to cyclin E and D

Answer 50

2,4,6

Question 51

which CDK binds to cyclin A

Answer 51

1,2

Question 52

which CDK binds to cyclin B

Answer 52

1

Question 53

what does cyclin A do

Answer 53

activates S phase and G2

Question 54

what does cyclin D and E do

Answer 54

G1 to S

Question 55

what does cyclin B do

Answer 55

G2 to M

Question 56

when does cyclin C activate

Answer 56

G0

Question 57

what regulates phase transitions

Answer 57

cyclins + CDKs

Question 58

what is the restriction point

Answer 58

G1 to S transition

Question 59

what supresses CDKs

Answer 59

CDKIs