cell cycle

Question 1

cell cycle

Answer 1

period of time betweeen the birth of a cell and its own divission to produce two new daughter cells

Question 2

cycling cells

Answer 2

Cells that continue to divide regularly in definite intervals

Question 3

what do cyclins activate

Answer 3

cyclin dependant kinases- cdks

Question 4

what happens to cyclins and cdks at the end of the cell cycle

Answer 4

they are dgeraded

Question 5

cyclins role

Answer 5

regulate cell cycle progression

Question 6

ubiquitin

Answer 6

takes up used molecules
is a care taker protein

Question 7

interphase

Answer 7

The interval between the end of mitosis and beginning of next

Question 8

s phase

Answer 8

period in which new dna is synthesised

Question 9

what is the s phase promoted by

Answer 9

cyclin a and cdks

Question 10

longest phase

Answer 10

g1

Question 11

g1

Answer 11

cell mostly grows

Question 12

does g1 have a checkpoint

Answer 12

yes

Question 13

if dna is damaged what happens

Answer 13

enters g0 phase where it is either repaired or carries out apoptosis

Question 14

when does dna replication occur

Answer 14

s phase

Question 15

what occurs during s phase

Answer 15

Each chromosome from g1 is replicated with help from enzymes, energy and structural proteins
Chromatid copied and pasted
Join at centromere
Still make up a single chromosome; amount of info doubled

Question 16

are more chromosomes made

Answer 16

no just more infomration is added

Question 17

g2 phase

Answer 17

second growth phase
cell duplicates organelles

Question 18

what happens post g2 phase

Answer 18

must pass g2 checkpoint to enter mitosis

Question 19

karyokinesis

Answer 19

dna seperated into 2 distinct nuceli

Question 20

cytokinesis

Answer 20

seperates daughter cells into 2 distinct cells

Question 21

prophase

Answer 21

nuclear membrane disintegrates and chromosomes condense and become visible
2 centromeres migrate to opposite ends

Question 22

metaphase

Answer 22

chromosomes migrate to middle of cell on metaphase plate
once in plane each centrosome sends out thread like prokections

Question 23

spindle fibres

Answer 23

the thread like projections that centrosomes send out to centromeres

Question 24

anaphase

Answer 24

centrosome starts pulling on spindle fibres to pull chromatids apart
sister chromatids seperate

Question 25

telophase

Answer 25

nuclear membranes form around chromosome cytokinesis ; cell membrane pinches until 2 daughters seperate

Question 26

when does crossing over occur

Answer 26

prohase 1

Question 27

what is g1 controlled by

Answer 27

cyclin e and cdks

Question 28

what controls g2 phase

Answer 28

cyclin b and cdks

Question 29

where does mitosis occur

Answer 29

somatic cells

Question 30

colchicine

Answer 30

arrests the cell division at metaphase prevents formation of microtubules of the spindle

Question 31

non disjunction

Answer 31

Due to abnormal function of spindle apparatus one or more chromosomes fail to migrate properly in anaphase one daughter cell recieves extra chromosomes and other daughter cell is deficient inthis chromosome

Question 32

isochromosome

Answer 32

Sometimes, the centromere splits transversely instead of longitudinal division. This leads to formation of two daughter chromosome of unequal length

Question 33

when does the nucleolus appear

Answer 33

telophase

Question 34

when do chromosomes become uncoiled and lose their indiviudal identity

Answer 34

telophase