Chapter 19.2

Question 1

What parts of cell cycle make up interphase

Answer 1

G1, S, G2

Question 2

what happens in G1

Answer 2

cell increases in size, nucleus moves to middle of cell, organelles divide

Question 3

what is G0

Answer 3

when arrested cells stay in G1 (neurons are example of this)

Question 4

what happens in S phase

Answer 4

DNA is replicated

Question 5

what happens in G2 phase

Answer 5

structures necessary for mitosis are produced

Question 6

steps of mitosis

Answer 6

prophase, prometaphse, metaphase, anaphase, telophase

Question 7

parts of prophase

Answer 7

chromosomes condense

cytoskeleton begins to disassemble

Question 8

centomere

Answer 8

constricted region of each chromatid where the sisters are attached

Question 9

centrosome

Answer 9

microtubule organizing center

Question 10

hallmarks of prometaphase

Answer 10

nuclear envelop disappears
nucleolus disappears
kinetochores develop
centrosomes move apart and spindle fibers appear

Question 11

Kinetochore MT

Answer 11

attach to chromosomes at kinetochores

Question 12

kinetochore

Answer 12

proteins associated with the centromere that acts as a handle for the spindle fibers

Question 13

Polar MT

Answer 13

interact with spindles from opposite pole

Question 14

Astral MT

Answer 14

form the asters at each pole which anchor centrosomes in place

Question 15

Features of metaphase

Answer 15

chromosomes are maximally condensed
chromatids line up on metaphase plate
cell seems to pause

Question 16

specifics of anaphase

Answer 16

sister chromatids separate at centromeres

move toward poles

Question 17

anaphase A movement

Answer 17

chromosomes pulled apart (toward centrosomes)

Question 18

anaphase B movement

Answer 18

poles themselves move apart

Question 19

steps of telophase

Answer 19

daughter chromosomes reach opposite poles
chromosomes uncoil (elongate)
nucleoli develop
spindle disassembles 
nuclear envelopes form
cell undergoes cytokinesis

Question 20

Roles of mitotic motors

Answer 20

move chromosomes
movement of spindle poles
exert a pull on spindle poles

Question 21

how do mitotic motors work

Answer 21

use energy from ATP to change shape

Question 22

basic steps of cytokinesis in animal cells

Answer 22

formation of cleavage furrows in early anaphase
belt-like bundle of actin microfilaments make a contractile ring
ring closes separating the cells

Question 23

what makes up the contractile ring during cytokinesis

Answer 23

actin microfilaments

Question 24

basic steps of cytokinesis in plant cells

Answer 24

microtubules organized into phragmoplast
directs cell wall material to form cell plate
made of vesicles from the golgi
formation of cell plate

Question 25

what is phragmosome

Answer 25

zone of cytoplasm between nuclei | where cell plate is formed

Question 26

what is phragmoplast

Answer 26

barrel shaped structure that directs cell wall material to form cell plate

Question 27

restriction point

Answer 27

checkpoint in late G1 that checks for specific nutrients and growth factor

Question 28

G2-M transition

Answer 28

commitment to mitosis once passed | checks for cell size and DNA replication

Question 29

metaphase-anaphase transition

Answer 29

commitment to separate chromosomes | checks for chromosome attachment to spindle

Question 30

maturation promoting factor (MPF)

Answer 30

induces meiotic cell division | aka mitotic CdK-cyclin complex

Question 31

what type of cells are karyotypes taken from

Answer 31

metaphase arrested

Question 32

what drug is used to make karyotypes

Answer 32

colchine | interferes with metaphse-anaphase transition by hindering MT

Question 33

function of mitotic cyclin

Answer 33

regulates progression through euk cell cycle | increased levels lead to activation of MPF and mitosis

Question 34

which is stable and which cycles

Answer 34

stable is CdK | cyclin cycles

Question 35

steps of activation of CdK-cyclin complex

Answer 35

1. mitotic CdK and cyclin form an incactive complex 2. inhibiting kinase adds 2 Phosphates which block active site 3. activating kinase adds third phosphate 4. phosphatase removes the 2 inhibiting Pi 5. CdK-cyclin becomes active 6. stimulates phosphatase to produce more active complexes

Question 36

why must cyclin be degraded after mitosis

Answer 36

otherwise it would induce the cell to go through mitosis before it is ready

Question 37

what happens to cyclin levels during interphase

Answer 37

increases at a steady rate