Chapter 18

Question 1

In eukaryotic cells, progression through the cell cycle is controlled by

Answer 1

protein kinases

Question 2

(nuclear division), usually ending with cell division (cytokinesis).

Answer 2

Mitosis (M phase)

Question 3

period between mitoses, divided into G1, S, and G2.

Answer 3

Interphase

Question 4

interval between mitosis and DNA replication. The cell is metabolically active and growing.

Answer 4

G1 phase

Question 5

DNA replication takes place.

Answer 5

S phase

Question 6

cell growth continues and proteins are synthesized in preparation for mitosis.

Answer 6

G2 phase

Question 7

_______ may have cell cycles of 30 minutes, but there is no growth (G1 or G2) phase.

Answer 7

Early embryos

Question 8

During S phase, replication increases the DNA content to:

Answer 8

4n

Question 9

______ controls progression from G1 to S, first defined in yeast

Answer 9

START

Question 10

Passage through START is highly regulated by _______, such as nutrient availability, mating factors and cell size.

Answer 10

external signals

Question 11

In most animal cells, ________ in late G1 functions like START.

Answer 11

restriction point

Question 12

If appropriate growth factors are not present in G1, progression stops at the restriction point and cells enter a resting stage called:

Answer 12

Gzero

Question 13

Coordination of the cell cycle phases is dependent on a series of

Answer 13

cell cycle checkpoints.

Question 14

ensure that damaged DNA is not replicated and passed on to daughter cells.

Answer 14

DNA damage checkpoints

Question 15

stops mitosis at metaphase if chromosomes are not properly aligned on the spindle.

Answer 15

Spindle assembly checkpoint

Question 16

a general regulator of transition from G2 to M.

Answer 16

maturation promoting factor (MPF).

Question 17

responsible for the progression of the cell cycle (2 things)

Answer 17

cyclins and CDK proteins

Question 18

Proliferation of animal cells is regulated by extracellular growth factors that control progression through the restriction point in:

Answer 18

late G1.

Question 19

_____cyclins provide one link between growth factor signaling and cell cycle progression.

Answer 19

D-type

Question 20

As long as ________ are present through G1, Cdk4,6/cyclin D1 complexes drive cells through the restriction point.

Answer 20

growth factors

Question 21

Cell cycle arrest at DNA damage checkpoints: (2 things)

Answer 21

ATM and ATR

Question 22

____ recognizes double-strand breaks; _____ recognizes single-stranded or unreplicated DNA.

Answer 22

ATM, ATR

Question 23

ATM and ATR phosphorylate and activate the checkpoint kinases, _______.

Answer 23

Chk1 and Chk2

Question 24

In mammalian cells, arrest at the G1 checkpoint is also mediated by this protein

Answer 24

p53

Question 25

mitosis phases

Answer 25

Prophase Metaphase Anaphase Telophase

Question 26

appearance of condensed chromosomes (two sister chromatids).

Answer 26

prophase

Question 27

The chromatids are attached at the:

Answer 27

centromere

Question 28

site of eventual spindle attachment

Answer 28

kinetochore

Question 29

Centrosomes serve as the two poles of:

Answer 29

mitotic spindle

Question 30

transition between prophase and metaphase.

Answer 30

prometaphase

Question 31

The chromosomes shuffle back and forth until they align on the ________ plate

Answer 31

metaphase

Question 32

links between sister chromatids break during this phase

Answer 32

anaphase

Question 33

nuclei re-form and chromosomes decondense.

Answer 33

telophase

Question 34

________ usually begins during late anaphase and is almost complete by the end of telophase.

Answer 34

Cytokinesis

Question 35

Cdk1/cyclin B protein kinase (MPF) is the master regulator of ___ phase transition.

Answer 35

M

Question 36

These 3 things are activated in a positive feedback loop to signal entry into M phase.

Answer 36

Cdk1, Aurora and Polo-like kinases

Question 37

contribute to chromosome segregation. (2 things)

Answer 37

condensins and cohesins

Question 38

Condensins are activated by Cdk1/cyclin B _________

Answer 38

phosphorylation

Question 39

The _________ fragments into vesicles at mitosis, which are absorbed into the ER or distributed to daughter cells at cytokinesis.

Answer 39

Golgi apparatus

Question 40

_________ maturation and spindle assembly involve the Aurora and Polo-like kinases.

Answer 40

Centrosome

Question 41

_________ turnover rate increases, resulting in depolymerization and shrinkage of the interphase microtubules.

Answer 41

Microtubule

Question 42

Unattached kinetochores lead to the assembly of the:

Answer 42

mitotic checkpoint complex (MCC)

Question 43

APC/C ubiquitylates cyclin B and securin, which inactivates Cdk1 and activate:

Answer 43

separase.

Question 44

Separase degrades ______, which breaks the link between sister chromatids

Answer 44

cohesin