Cell Membrane & Transport, Receptors & Messengers Flashcards Preview

Physiology 1 - Ashley > Cell Membrane & Transport, Receptors & Messengers > Flashcards

Flashcards in Cell Membrane & Transport, Receptors & Messengers Deck (13)
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1
Q

What’s the difference between steady state and equilibrium?

A

Steady state requires energy of Na/K ATPase pump to offset the leak of Na in and K out of the cell.
Equilibrium does NOT require energy - passive distribution of ions/substances.

2
Q

What powers facilitated transport? Example?

A

DIFFUSION - no energy required. It’s the movement of a substance through a transmembrane protein down the substance’s gradient. Example - glucose

3
Q

On which side of the cell are Na/K ATPase proteins located?

A

RULE: Na/K ATPase is only on the basolateral membrane (the side away from the lumen).

4
Q

How long does it take for the total membrane of a cell to turn over? Why does it do this?

A

Takes about an hour - this rate accounts for the ability to reconfigure the type of proteins (channels, transporters, receptors, etc) in the membrane in relatively short order.

5
Q

What’s the most important second-messenger system?

A

cAMP

6
Q

How can cAMP have such diverse mechanisms of action within a cell?

A

cAMP diffuses throughout the cell to bind to cAMP-dependent kinases (PKA), and PKA phosphorylates a variety of enzymes throughout the cytosol

7
Q

What are two second messengers derived from plasma membrane phospholipids?

A
  • -IP3, DAG (formed by action of phospholipase C on PIP2)

- -Arachidonic acid (formed by action of phospholipase A2 on membrane phospholipids)

8
Q

Name the second messenger and the kinase associated with:

adenylyl cyclase

A

cAMP

protein kinase A

9
Q

Name the second messenger and the kinase associated with:

guanylyl cyclase

A

cGMP

protein kinase G

10
Q

Name the second messenger and the kinase associated with:

phospholipase C

A

IP3 (regulating calcium), DAG

protein kinase C

11
Q

Name the second messenger and the kinase associated with:

phospholipase A2

A

arachidonic acid

cyclooxygenase, lipoxygenase

12
Q
Which of the following processes directly utilizes ATP?
A. facilitated diffusion
B. primary active transport
C. secondary active transport
D. all require ATP
A

B. only primary active transport utilizes ATP

13
Q

The fastest axonal conduction speeds are reserved for:
A. somatic efferents and afferents
B. autonomic efferents
C. visceral afferents

A

A. somatic efferents and afferents

Autonomic efferents are largely unmyelinated