cell cycle

Question 1

new cells are clones…

Answer 1

same DNA of original cells (except reproductive cells)

Question 2

cell cycle phases

Answer 2

Cell division
Cells performing normal functions

Question 3

chromosomes

Answer 3

pieces of DNA

Question 4

somatic cells

Answer 4

everything that is not a reproductive cell

Question 5

somatic cells contain…

Answer 5

46 chromosomes, 23 pairs

Question 6

where do cells spend most time?

Answer 6

interphase; performing normal functions

Question 7

interphase: cells begin preparations for

Answer 7

division

Question 8

interphase subphrases:

Answer 8

G1, S, G2

Question 9

G1:

Answer 9

first gap phase: growth and organelles copied

Question 10

S:

Answer 10

synthesis phase: DNA is copied

Question 11

G2:

Answer 11

second gap phase: proteins made that assist division

Question 12

mitosis produces..

Answer 12

exact copies of parent cell nucleus (in somatic cells)

Question 13

big pic of mitosis:

Answer 13

reorganization of chromosomes into new cells

Question 14

stages of mitosis:

Answer 14

• 1. Prophase
• 2. Metaphase
• 3. Anaphase
• 4. Telophase

Question 15

mitotic spindle function

Answer 15

arranges chromosome during division

Question 16

mitotic spindle: centrosome

Answer 16

o In animal cells
o Microtubules grow outward
o Support cell shape and assists with cell division

Question 17

mitotic spindle: kinetochore

Answer 17

o Center of chromosomes
o Connects identical sister chromatids
o Attachment site for microtubules

Question 18

what occurs during prophase?

Answer 18

*Chromosomes condense
*Mitotic spindle forms
-Centrosomes move apart

Question 19

what happens between prophase and metaphase (pro-metaphase)?

Answer 19

*Nuclear envelope breaks down
*Chromosomes become completely condensed
*Microtubules attach to kinetochores/lengthen cell

Question 20

where are centrosomes during metaphase

Answer 20

at opposite sides of cells

Question 21

what do chromosomes do during metaphase

Answer 21

each chromosome attached to both centrosomes

Question 22

metaphase plate

Answer 22

region where chromosomes are lined up by microtubules (center of cell)

Question 23

anaphase: chromosome copies…

Answer 23

separate

Question 24

telophase and cytokinesis

Answer 24

• Nucleus forms at each end
• Chromosomes become less condensed
• Cytoplasm divides

Question 25

cytokinesis:

Answer 25

physically separating original cell into 2 daughter cells *Microtubules are removed

Question 26

how to prokaryotes undergo "cell division"

Answer 26

binary fission: *Form of asexual reproduction *Cells elongates, duplicates chromosome (sometime just 1) and splits in half forming 2 new individuals

Question 27

cell cycle control system:

Answer 27

coordinates key events in cell cycle

Question 28

cell cycle stops at...

Answer 28

specific checkpoints: G1, G2, metaphase

Question 29

cell cycle progression is managed by

Answer 29

cyclic proteins

Question 30

G1 checkpoint:

Answer 30

determines if cell will continue dividing -ensure cell has proper nutrients -check if more cells are needed (presence of growth factor?)

Question 31

g1 checkpoint: if growth factors are NOT around and division should not occur...

Answer 31

they go into G0 phase ( can go back to G1 if growth factors are present again)

Question 32

G2 checkpoint:

Answer 32

ensures DNA has copied properly (2 complete copies of DNA)

Question 33

M checkpoint:

Answer 33

ensures all chromosome kinetochores are connected to microtubules

Question 34

density dependent inhibition

Answer 34

if closely packed, they will not keep dividing

Question 35

anchorage dependence

Answer 35

cells only divide if they are attached to something

Question 36

Cycle checkpoints are regulated by proteins, but

Answer 36

mutations may make a protein that does not work right

Question 37

Mutations in cell cycle regulating proteins may lead to

Answer 37

unregulated cell cycle, which can lead to tumors or cancer

Question 38

cancer cells lose...

Answer 38

density dependent inhibition: continue to divide even when closely packed with other cells (tumors form very dense tissue)

Question 39

tumor:

Answer 39

uncontrolled cell growth formed by one abnormal cell that evaded immune system

Question 40

benign tumor

Answer 40

cannot leave original location

Question 41

malignant tumor/cancer

Answer 41

can lose cells that spread to new locations (metastasis)

Question 42

o Chemotherapy interferes with

Answer 42

cell cycle: blocks cell division to let immune system get ahead of cancer cells -Hurts cancer cells most since they are dividing fastest