Smooth Muscle Physiology Flashcards Preview

Physiology (Autonomic Nervous System and Muscle) > Smooth Muscle Physiology > Flashcards

Flashcards in Smooth Muscle Physiology Deck (17)
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1
Q

How does smooth muscle control the vascular system?

A

Regulation of blood pressure

2
Q

How does smooth muscle control airways?

A

Constriction and relaxation

3
Q

How does smooth muscle control GI tract?

A

Peristalsis, segmentation, and transit

4
Q

How does smooth muscle control the gallbladder and urinary bladder?

A

Storage and emptying

5
Q

How does smooth muscle control the uterus?

A

Accommodation and delivery

6
Q

Difference between skeletal and smooth muscle

A

Skeletal muscle has sarcomeres and striations, smooth muscle does not

7
Q

Which is faster, skeletal or smooth muscle?

A

Skeletal muscle (0.2s vs smooth muscle 70s)

8
Q

Which uses less energy, skeletal or smooth muscle?

A

Smooth muscle (1.2umol vs skeletal muscle 50umol)

9
Q

Difference in release of calcium in skeletal vs smooth muscle

A

Skeletal: T-tubules to quickly propagate AP, calcium released
Smooth: calveoli (invaginations) propagate AP. triggers calcium release

10
Q

3 types of calcium channels in smooth muscle

A

Voltage gated
Ligand gated
IP3 gated

11
Q

How is calcium removed after contraction?

A

Removed by Ca-ATPase

12
Q

How are thick filaments regulated in smooth muscle?

A

ACh binds M3 receptor, calcium channels opened. Calcium binds to calmodulin which binds to MLCK, complex regulates thick filaments

13
Q

Explain length-tension curve

A

As you increase muscle length, you increase muscle output, but only up to a certain point. Then muscle becomes too stretched.

14
Q

Explain pressure-volume curve

A

Similar to length-tension (pressure = force output, volume = length)

15
Q

Explain force-velocity curve

A

Increase in force (due to heavy load) decreases velocity

16
Q

Phasic contraction

A

Periodically contracts and relaxes

Ex: proximal portion of stomach to move food down the tract

17
Q

Tonic contraction

A

Is relaxed and then contracts for a long time

Ex: sphincters of GI tract