1.3 Cell signalling

Question 0

Define endocrine signaling

Answer 0

Hormone secretion into blood by endocrine gland

Question 1

Name the 4 approaches to cell signaling

Answer 1

1. Endocrine signaling
2. Paracrine signaling
3. Autocrine signaling
4. Plasma membrane-attached proteins

Question 2

Define Paracrine signaling

Answer 2

Secretory cell signaling to adjacent target cell

Question 3

What type of signaling has target sites on the same cell?

Answer 3

Autocrine signaling

Question 4

What is bound to the inactivated G-protein subunit before it binds to the receptor

Answer 4

GDP

Question 5

An activated receptor causes conformation change in G-protein triggering what action?

Answer 5

The dissociation of GDP

Question 6

What finally activates the G-protein after it has been bound to the receptor

Answer 6

G-protein binds GTP and becomes activated

Question 7

What enzyme catalyzes the conversion of ATP into cAMP

Answer 7

Adenylate cyclase

Question 8

What causes the dissociation of G-protein from Adenylate Cyclase

Answer 8

Hydrolysis of GTP to GDP

Question 9

cAMP activates what?

Answer 9

Protein Kinase A

Question 10

What are the two actions of Protein Kinase A

Answer 10

1. Phosphorylates Serine & Threonine residues in many targets to alter their activity
2. Stimulates expression of CREB

Question 11

What two things end transduction

Answer 11

1. Dissociation of Ligand

2. Phosphorylation of C-terminal tail of receptor and subsequent binding of B-arrestin