Exam 4 Part 2

Question 1

mitogens

Answer 1

bind to receptor to create a signaling pathway that has an effect on cell proliferation

Question 2

Rb protein

Answer 2

transcription regulator that can be activated by a mitogen

Question 3

survival factors

Answer 3

activate a signaling pathway that blocks cell death

Question 4

Bcl2 gene

Answer 4

activated by survival factors that blocks apoptosis

Question 5

Growth factors

Answer 5

(In bovine serum) - signals a pathway to lead to cell growth (not necessarily proliferation)

Question 6

microtubules in cell division

Answer 6

make up the mitotic spindle
kinetochore microtubules
interpolar microtubules
aster microtubules

Question 7

micofilaments in cell dvision

Answer 7

actin and myosin make up the contracile ring

Question 8

phragmoblasts

Answer 8

in plants - vesicles that start the building of a cell wall

Question 9

kinetochore microtubules

Answer 9

physically attach to chromosomes and pull them apart

Question 10

aster microtubules

Answer 10

keeps attached to and anchors centrosomes

Question 11

interpolar microtubules

Answer 11

uses a pushing actin with dynein to push apart cells

also need to lengthen to continue the movement

Question 12

why do cells die?

Answer 12

for development (fingers), neuronal cells need to die for proper communications, cell infected with a virus and kills itself to stop spread - epithelial cells shed - frog development from tadpole

Question 13

When is cell dead?

Answer 13

Cell has lost plasma membrane integrity (with incorporation of dye)
Cell and nucleus has undergone complete fragmentation into descrete bodies
Corpse or fragments have been engulfed by an adjacent cell in vivo

Question 14

necrosis

Answer 14

mechanical cell death from damage

spills contents into surroundings which can damage other cells

Question 15

apoptosis

Answer 15

choice to undergo death
usually clean and compartmentalized
doesn’t damage neighboring cells
allows from recycling of components

Question 16

intrinsic apoptosis

Answer 16

cell senes something wrong within cell and signals death

DNA damage, ER stress, too short telomeres, etc

Question 17

extrinsic apoptosis

Answer 17

signals from outside environment signals death

Question 18

procaspase

Answer 18

cleaved through proteolysis and signaled to cleave by an extrinsic apoptosis receptor
cleavage of these activates and commits the cell to death
can activate more caspases or other things for death

Question 19

proteolysis

Answer 19

cleavage of procaspases to start apoptosis

Question 20

Bax/Bak

Answer 20

two different activating proteins that are stimulated by intrinstic apoptosis. Causes mitochondria to release cytochrome C

Question 21

cytochrome C

Answer 21

e transporter in mitochondria. Leaves the organelle by Bax/Bak signaling.
Bind to an adaptor protein which assembles into an apoptosome

Question 22

apoptosome

Answer 22

assembly of adaptor proteins attached to cytochrome C -and procaspase 9
activated by proteolysis of procaspase 9 to continue apoptosis