SAC cell signalling and apoptosis

Question 1

characteristics of apoptosis

Answer 1

cell shrinkage 
blebbing 
nuclear fragmentation
chromatin condensation 
chromosomal DNA fragmentation

Question 2

the 2 types of signals resulting in apoptosis

Answer 2

intrinsic (mitochondrial pathway)

extrinsic (death receptor pathway)

Question 3

the 2 types of signal transduction

Answer 3

hydrophobic

hydrophilic

Question 4

hydrophilic transduction

Answer 4

cannot easily diffuse through the phospholipid bilayer of the plasma membrane - receptor on the surface of the cell

Question 5

hydrophobic transduction

Answer 5

lipid based hormone - steroid

can easily pass through the phospholipid bilayer - not repelled - receptor on the inside of the cell

Question 6

ligand

Answer 6

signalling molecule

Question 7

stimulus response model

Answer 7

stimulus
receptor
effector
response

3 step process
reception
transduction
cellular response

Question 8

death receptor pathway

Answer 8

fasL fas ligand 
fasR fas receptor 
FADD fas associated protein death domain
caspase 8 (enzyme)
caspase 3 
trimer - 3 proteins joining together

Question 9

GPCR

Answer 9

G protein couple receptor

Question 10

hormones

Answer 10

secreted by endocrine glands distant to the target cell - secreted directly into the blood stream

Question 11

neurotransmitters

Answer 11

secreted by neutrons adjacent to the target cell - nerve cells

Question 12

cytokines

Answer 12

secreted by and for immune cells - secreted by white blood cells primarily

Question 13

pheromones

Answer 13

secreted by glands in another organism to the target cell - travel through the air

Question 14

endocrine signalling

Answer 14

produced in one part of the body and taken to a ‘target cell’ in another part of the body - distant from the target cell
0 ——————> 0

Question 15

paracrine signalling

Answer 15

signalling in which cells communicate over relativey short distances (adjacent)

Question 16

autocrine signalling

Answer 16

In autocrine signaling, a cell signals to itself, releasing a ligand that binds to receptors on its own surface (or, depending on the type of signal, to receptors inside of the cell).

Question 17

plant hormones

Answer 17

auxins 
gibberellins 
cytokinins
ethylene
abiscsic acid

Question 18

auxins

Answer 18

cause cell elongation - responsible for plants growing towards the light

Question 19

gibberellins

Answer 19

cause growth in tissues by causing the cells to get longer

Question 20

cytokinins

Answer 20

cause growth by stimulating plant cells to divide through mitosis

Question 21

ethylene

Answer 21

cause fruit ripening

flower buds to open

Question 22

abiscisic acid

Answer 22

acid - stomatal closure

the closure o the stomata on the surface of the leaf

Question 23

differences to animal hormones (plant)

Answer 23

DO NOT travel in general circulation
are NOT produced in endocrine glands
are NOT biomacromolecules