Module 3: cell communication and receptor families

Question 1

What are the 2 broad types of cell communication?

Answer 1

1. local signalling
2. long distance signalling

Question 2

what are the two types of local signalling?

Answer 2

1. paracrine signalling
2. synaptic signalling

Question 3

what are the types of long-distance signalling?

Answer 3

1. endocrine signalling

Question 4

what is paracrine signalling?

Answer 4

1. one cell releases a signalling molecule that acts on nearby cells
2. immune system

Question 5

what is synaptic signalling?

Answer 5

1. main method of communication between neurons

Question 6

what is endocrine signalling?

Answer 6

1. signalling molecule released from a cell into the bloodstream
2. hormone

Question 7

what are the three stages of cell signalling?

Answer 7

1. reception (signalling molecule binds to a specific receptor)
2. transduction (signalling pathway is initiated in the cytoplasm)
3. response (cellular response is activated)

Question 8

what are the four families of receptors?

Answer 8

1. ligand-gated ion channel (fast/direct)
2. G protein-coupled receptor (slower/indirect)
3. tyrosine kinase receptor
4. steroid receptor

Question 9

What is a ligand-gated ion channel

Answer 9

1. involved in synaptic transmission
2. ion channels in membrane opened by binding of a ligand
3. when opened ions flow into/out of cell
4. directly changes the voltage across the membrane during synaptic transmission, triggering ISPSs and ESPSs
5. fast response

Question 10

What are the features of G protein coupled receptors?

Answer 10

1. Over 1000 types, most of which we don’t know the activation: orphan receptors
2. > 50% of current drugs target them
3. Are involved in neuronal and Hormonal signaling

Question 11

What does a G protein coupled receptor look like?

Answer 11

1. Has a receptor outside of the cell
2. Has 7 transmembrane domains that the proteins flows through
3. Had the G protein inside the cell

Question 12

What does phosphorylation do?

Answer 12

Controls the activity of proteins by the use of a kinase or phosphatase enzymes

Question 13

How does phosphorylation affect g proteins?

Answer 13

They are either turned on or off by phosphorylation or dephosphorylation

Question 14

What is signal amplification?

Answer 14

When small quantities of signaling molecules create large effects in the cell

Question 15

What is the name of the process that creates chemical exponential growth?

Answer 15

Signal amplification

Question 16

What are the 8 nuerotransmitters

Answer 16

1. adrenaline
2. noradrenaline
3. dopamine
4. serotonin
5. gaba
6. acetylcholine
7. glutamate
8. endorphins

Question 17

Which receptors are hydrophobic?

Answer 17

Steroid receptors