Week 3- the autonomic nervous system Flashcards

1
Q

What does the release of acetylcholine do to heart rate?

A

Decreases HR

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What causes low resting heart rate?

A

Parasympathetic tone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the initial increase in HR due to?

A

parasympathetic withdrawal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is end diastolic volume (EDV)?

A

Volume of blood in the ventricles at the end of diastole (‘preload’)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is the average aortic blood pressure?

A

Pressure heart must pump against to eject blood (‘afterload’)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What does an increase in cardiac afterload cause?

A

decrease in SV during resting where the influences on cardiac contractility are not at play

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the strength of the ventricular contraction enhanced by?

A

-circulating epinephrine and norepinephrine
-direct sympathetic stimulation of the heart

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What does a greater end diastolic volume result in?

A

A more forceful contraction due to strength of ventricles but is dependent on the rate of venous return

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is venous return increased by?

A

-vasoconstriction
-skeletal muscle pump
-respiratory pump

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is cardiac output?

A

amount of blood pumped by the heart each minute

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the cardiac output equation?

A

Q = HR x SV

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What factors regulate cardiac output?

A

-PNS decreases Q
-SNS increases Q
-Stoke volume decreases Q

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

When is systolic pressure generated?

A

during ventricular contraction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is diastolic pressure?

A

pressure in the arteries during cardiac relaxation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is pulse pressure?

A

The difference between systolic and diastolic blood pressure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is mean arterial pressure (MAP)?

A

Average pressure in the arteries

17
Q

What are the determinants of mean arterial pressure?

A

-cardiac output
-total vascular resistance (sum of resistance to blood flow)
-MAP=Q x total vascular resistance

18
Q

What are the short term regulators of mean arterial pressure?

A

-SNS
-Baroreceptors in aorta and carotid arteries

19
Q

What are the long term regulators of mean arterial pressure?

A

Kidneys via a control of blood volume

20
Q

How is the blood flow delivery to exercising muscles increased?

A

-cardiac output increase
-redistribution of blood flow from inactive organs to working muscles

21
Q

What do changes in HR and BP depend on?

A

Type, intensity, duration, environmental conditions, emotional influence pre-exercise and during submaximal exercise due to increased SNS