lecture 16 redone

Question 1

calcium prevents polyseprming by

Answer 1

raising fertilisation envelope

Question 2

why is calcium used in so many processes

Answer 2

to keep calcium levels low becuase calcium phosphate is highly insoluble

Question 3

OFF mechanism 1 - Ca-ATPase pump

Answer 3

pumps calcium ions out the cell against concentration gradient
PMCA - on the plasma membrane
SERCA - on the membrane of ER/SR

Question 4

OFF mechanism 2 - Na/Ca exchanger
what is it driven by

Answer 4

the inward sodium gradient

Question 5

3 OFF mechanism - mitochondria

Answer 5

uptakes calcium ions

Question 6

OFF mechanism 4 - proteins bind to calcium ions

Answer 6

eg buffers

Question 7

intracellular calcium ion channel in the membrane of the ER/SR is called the

Answer 7

IP3 receptor

Question 8

when the IP3 receptor is activated

Answer 8

calcium comes rushing out the ER/SR into the cytosol

Question 9

what are the 3 types of calcium signal

Answer 9

1. elementary events
   2.global calcium wave (intracellular)
2. global calcium wave (intercellular)

Question 10

what are elementary events

Answer 10

calcium rise in one specific location of the cell

Question 11

global calcium wave (intracellular)

Answer 11

calcium wave begins in one part of the cell and makes its way across the rest of the cell

Question 12

global calcium (intercellular)

Answer 12

propagates throughout a monolayer of cells

Question 13

PI pathway
chemical signal induces a conformational change in the receptor activating

Answer 13

G protein

Question 14

G protein stimulates

Answer 14

the amplifier Phospholipase C (PLC)

Question 15

G protein stimulates

Answer 15

the amplifier Phospholipase C (PLC)

Question 16

PLC acts on

Answer 16

PIP2 to give DAG and IP3 (second messengers)

Question 17

DAG stay on the plane of the kipid bilayer and stimulates

Answer 17

protein kinase C

Question 18

IP3 diffuses into the cytosol where it acts on its receptor to release

Answer 18

calcium from stores