PE- Regulating HR (DONUGHUE)

Question 1

Why does heart rate increase?

Answer 1

Hormonal= increase in adrenaline
Neural= receptors in your body tell the brain your heart needs to increase stroke volume 
Intrinsic= when you exercise, you get warmer, increases heart rate

Question 2

How is the heat rate controlled? Give 6 knowledge points:

Answer 2

CCC found in the medulla oblongala of the brain
Controlled by the autonomic nervous system
Sensory + motor nerves from sympathetic or parasympathetic nervous system
Sympathetic nerves increase HR
Parasympathetic nerves decrease HR
CCC initiates sympathetic or parasympathetic nerves to stimulate SA node to increase or decrease HR

Question 3

Name 3 aspects of neural control?

Answer 3

Proprio-receptors= sense that movement has increased 
Chemoreceptors= sense when chemicals like co2 + lactic acid have increase 
Baroreceptors= sense when blood pressure has increased

Question 4

Name 2 aspects of hormonal control?

Answer 4

Before and after exercise adrenaline is released in the blood
This then stimulates SA node to increase HR

Question 5

Name 2 aspects of intrinsic control?

Answer 5

During exercise temperature increases which increases the speed of nerve impulses which increases HR
Venous return increases HR which stretches the heart (myocardium) which therefore increases EDV and SV