Week 3 - Nervous System (Autonomic)

Question 1

Describe the role of the autonomic nervous system

Answer 1

The autonomic nervous system regulates processes like heart rate, blood pressure, respiration, digestion, and sexual arousal involuntarily

Question 2

What are the main neurotransmitters in the ANS system

Answer 2

S2-S4 is ACh
T1-T2 is ACh & NE
T10-L1 is ACh

Question 3

How does the nervous system regulate heart rate during exercise onset

Answer 3

Initially, heart rate increases due to parasympathetic withdrawal, followed by an increased due to increased sympathetic nervous system outflow

Question 4

Define end-diastolic volume

Answer 4

Volume of blood in the ventricles at the end of diastole

Question 5

Define Frank-Starling mechanism

Answer 5

Greater end-diastolic volume results in a more forceful contraction due to stretch of the ventricles

Question 6

Define average aortic blood pressure

Answer 6

Pressure the heart must pump against to eject blood (Mean arterial pressure)

Question 7

How is the strength of the ventricular contraction enhanced by

Answer 7

Circulating epinephrine and norepinephrine
Direct sympathetic stimulation of the heart

Question 8

What factors are involved in the regulation of venous return

Answer 8

Venoconstriction (SNS)
Skeletal muscle pump (Rhythmic skeletal muscle contractions)
Respiratory pump (Changes in thoracic pressure)

Question 9

Define cardiac output

Answer 9

The amount of blood pumped by the heart each minute
Q = Heart rate x Stroke volume

Question 10

Define systolic pressure

Answer 10

Pressure generated during ventricular contraction

Question 11

Define diastolic pressure

Answer 11

Pressure in the arteries during cardiac relaxation

Question 12

Define pulse pressure

Answer 12

Difference between systolic and diastolic pressure

Question 13

Define mean arterial pressure

Answer 13

Average pressure in the arteries

Question 14

What are the determinants of mean arterial pressure

Answer 14

Cardiac output
Total vascular resistance
MAP = CO x TVR

Question 15

How is arterial blood pressure regulated

Answer 15

Short term: SNS activity & Baroreceptors
Long term: Kidneys through control of blood volume

Question 16

What are the two changes in cardiovascular variables during exercise onset

Answer 16

Increase in cardiac output
A redistribution of blood flow form inactive organs to working skeletal muscle

Question 17

What non-physiological factors affect changes in heart rate and blood pressure

Answer 17

Type, intensity and duration of exercise
Environmental conditions
Emotional influence

Question 18

What physiological transitions occur from rest to exercise & exercise to recovery

Answer 18

Onset of Exercise: Rapid increase in HR, stroke volume and cardiac output
Plateau in submaximal exercise
During recovery: Decrease in HR, stroke volume and cardiac output

Question 19

What factors affect the rate of recovery in factors such as HR and BP after intermittent exercise

Answer 19

Fitness level
Temperature & humidity
Duration & intensity of exercise

Question 20

What happens to heart rate, cardiac output and blood pressure during incremental exercise

Answer 20

Heart rate & cardiac output: Increases linearly with increasing work rate
Reaches plateau at 100% VO2 max
Blood pressure increases linearly: Systolic blood pressure increases, diastolic blood pressure stays constant