14.7 - Control of Heart Rate

Question 1

What does myogenic mean?

Answer 1

Contraction initiates within the muscle itself

Question 2

What structures does the wave of electrical excitation travel through?

Answer 2

SAN

Question 3

What is the role of the SAN?

Answer 3

Initiates heartbeat

Question 4

What is the role of the AVN?

Answer 4

Delays electrical activity

Question 5

What is the role of the Bundle of His?

Answer 5

Conducts excitation to apex

Question 6

What is the role of Purkyne fibres?

Answer 6

Cause ventricles to contract from bottom up

Question 7

What controls the heart rate?

Answer 7

Medulla oblongata

Question 8

What receptors does the medulla oblongata receive information from?

Answer 8

Baroreceptors and chemoreceptors

Question 9

What do baroreceptors detect?

Answer 9

Blood pressure

Question 10

What do chemoreceptors detect?

Answer 10

Chemicals

Question 11

What neurotransmitter is used by the parasympathetic pathway?

Answer 11

Acetylcholine

Question 12

What neurotransmitter is used by the sympathetic pathway?

Answer 12

Noradrenaline

Question 13

What is the effect of high blood pressure on the SAN?

Answer 13

Decreased electrical activity

Question 14

What is the effect of low blood pressure on the SAN?

Answer 14

Increased electrical activity

Question 15

What is the effect of high O2

Answer 15

low CO2

Question 16

What is the effect of low O2

Answer 16

high CO2

Question 17

How does the autonomic nervous system respond during exercise?

Answer 17

Chemoreceptors detect high CO2

Question 18

What hormones can influence heart rate?

Answer 18

Adrenaline and noradrenaline