Cell Cycle 2

Question 1

What happens during mitosis?

Answer 1

condensation of chromosomes
assembly of mitotic spindles
breakdown of nuclear envelope
attachment of chromatids to spindle

Question 2

What does condensin do?

Answer 2

forms ring like structure and uses ATP to promote compaction and resolution of sister chromatids

Question 3

_____ triggers the assembly of mitotic spindle

Answer 3

M-Cdk

Question 4

Microtubules are made of _____ subunits

Answer 4

tubulin

Question 5

What is tubulin?

Answer 5

a hetero dimer of alpha and beta tubulin with nonconvalent bonds

Question 6

The plus end of a microtubule is _______ growing, and the minus end is _____ growing

Answer 6

fast; slow

Question 7

What are the three types of microtubules?

Answer 7

kinetochore microtubules
interpolar microtubules
astral microtubules

Question 8

What do kinetochore microtubules do?

Answer 8

attach each chromosome to spindle pole

Question 9

What do inter polar microtubules do?

Answer 9

hold two halves of spindle together

Question 10

What do astral microtubules do?

Answer 10

interact with cell cortex

Question 11

The plus end of ______ microtubules are attached to sister chromatid pairs at large protein structures called kinetochores and to centromere

Answer 11

kinetochores

Question 12

plus end of ____ microtubules coming from one pole interact with plus ends from other pole

Answer 12

interpolar

Question 13

_____ microtubules radiate outward from the poles and contact the cell cortex helping to position the spindle in the cell

Answer 13

astral

Question 14

Where are microtubules nucleated from?

Answer 14

microtubule organizing center (MTOC)

Question 15

What is y-tubulin involved in?

Answer 15

nucleation of microtubule growth

Question 16

y- tubulin ring complex (y-TuRC) is responsible for what?

Answer 16

nucleation of microtubule growth

Question 17

What does y-turc bind to?

Answer 17

negative end to nucleate and elongate microtubules

Question 18

Protein organelles are called ______ and consist of matrix and a pair of ______

Answer 18

centrosomes; centrioles

Question 19

Dyneins move to _____ of cell and are ____ end directed

Answer 19

center; minus

Question 20

Kinesins move toward ____ of cell, and walk toward ____ end of microtubules

Answer 20

periphery; plus

Question 21

What is kinesin-5?

Answer 21

two motor domains that interact with plus end of anti parallel microtubule

Question 22

Kinesin-5 motors move two anti parallel microtubules past each other to for or push the spindle pole ____

Answer 22

apart

Question 23

PINK walks toward ____

Answer 23

plus end to force centrosomes apart

Question 24

What is kinesin 14?

Answer 24

minus oriented directed motor with a single motor domain

Question 25

What is kinesin 4, 10?

Answer 25

also called chromokinesin, plus directed motors

Question 26

What is a class 1 extracellular signaling molecule?

Answer 26

mitogens: stimulate cell division by triggering G1/S -Cdl activity

Question 27

What is a class 2 extracellular signaling molecule?

Answer 27

growth factors- stimulate cell growth

Question 28

What is a class 3 extracellular signaling molecule?

Answer 28

survival factors- suppress form of programmed cell death (apoptosis)

Question 29

What is Rb? and how can mutation lead to retinoblastoma?

Answer 29

tumor suppressor

if there are loss of copies of the Rb gene, then it can lead to cell and tumor proliferation of retina

Question 30

What does ATM do?

Answer 30

senses DNA damage

Question 31

What are the substrates of ATM? what do they activate?

Answer 31

Chk1 and Chk2 which activate p53

Question 32

What are the three mechanisms to coordinate cell growth with division?

Answer 32

1. rate of cell division determined by extracellular factor leading to cell growth
2. cell growth and division controlled separately by growth factors and mitogens
3. cell growth and division both stimulated by extracellular factor