Unit 4b - Cell Cycle

Question 1

Why do cells Divide?

Answer 1

reproduction
growth
tissue Repair

Question 2

What does a Centriole do?

Answer 2

aid in cell division

Question 3

Genome

Answer 3

all of a cell’s genetic material

Question 4

What are the parts of a Chromosome?

Answer 4

centromere
sister chromatids
spindle fibers (attached to kinetochore)
kinetochore

Question 5

Somatic Cells

Answer 5

body cells
diploid (2n): 2 of each type of chromosome
divide by mitosis
Human (2n): 46

Question 6

Gamete Cells

Answer 6

sex cell (sperm/egg)
haploid (n): 1 of each type of chromosome
divide by meiosis
Human (n): 23

Question 7

Interphase makes up …..

Answer 7

90% of the cell cycle.

Question 8

Phases of Interphase

Answer 8

G1 , S , G2

Question 9

G1

Answer 9

cell grows and carries out normal functions

Question 10

S

Answer 10

duplicated chromosomes

Question 11

G2

Answer 11

prepares for cell divisions

Question 12

M Phase (Mitotic Phase)

Answer 12

Mitosis
Cytokinesis

Question 13

Mitosis

Answer 13

nucleus divides

Question 14

Cytokinesis

Answer 14

cytoplasm divides

Question 15

What are the 5 phases of Mitosis? (PMAT)

Answer 15

prophase
metaphase
anaphase
telophase

Question 16

What is not a phase of Mitosis?

Answer 16

interphase

Question 17

Prophase

Answer 17

chromosomes become visible and nucleus dissolves

Question 18

Metaphase

Answer 18

chromosomes line up in the middle of the cell

Question 19

Anaphase

Answer 19

sister chromatids separate and move away from each other.

Question 20

Telophase

Answer 20

2 nuclei in one cell

Question 21

What does cytokinesis in Animal cells look like?

Answer 21

clevage furrow

Question 22

What does cytokinesis in Plant cells look like?

Answer 22

cell plate

Question 23

How do Bacteria divides?

Answer 23

binary fission

Question 24

What is a Checkpoint?

Answer 24

control point where stop/go signals regulate the cell cycle.

Question 25

What are the Major Checkpoints?

Answer 25

G1 , G2 , M-spindle

Question 26

What happens at the G1 Checkpoint . (most important)

Answer 26

controlled by cell size , growth factors , and environment.
- “Go” –> completes the cell cycle
- “Stop” –> cell centers non dividing state (G0)

Question 27

What happens at the G2 Checkpoint?

Answer 27

controlled by DNA replication completion , DNA mutations , cell size.

Question 28

What happens in the M- spindle Checkpoint ?

Answer 28

check spindle fiber attachment to the kinetochore

Question 29

What are the THREE internal regulatory molecules?

Answer 29

Cyclin
CDKs
MPF

Question 30

What do CDK ( cyclin dependent kinases ) do?

Answer 30

controls the cell cycle ; active only when connected to cyclin.

Question 31

What does Cyclins do?

Answer 31

regulate the fluctuation of levels in the cell cycle

Question 32

What do MPF (maturation promoting factors) do?

Answer 32

-cyclin -cdk complex
allows cells to pass G2 and go to M phase.

Question 33

What are the THREE external regulatory factors?

Answer 33

growth factor
density dependent inhibition
anchorage dependence

Question 34

What do/are Growth Factors?

Answer 34

proteins released by other cells to stimulate cell division.

Question 35

What do/are Density Dependent Inhibition?

Answer 35

cell surface protein binds to adjoining cell to inhibit growth.

Question 36

What do/are Anchorage Dependence?

Answer 36

cells must be attached to another cell or extra cellular structure to divide.

Question 37

Define Cancer

Answer 37

a disorder in which cells lose the ability to control growth by not responding to regulation.

Question 38

Cancer cells …

Answer 38

lose anchorage dependency and density dependent regulation.
– they divide without structure and without intercellular communication.