CV System

Question 1

How can blood be redistributed in the body?

Answer 1

1. Exercise begins
2. Increase in CO2 / Acidity, Blood pressure and Movement
3. Detected by receptors: Chemoreceptors (CO2), Baroreceptor (Blood pressure) and Proprioceptor (Movement)
4. Nerve impulse sent to Medulla Oblongata
5. Nerve impulse along sympathetic nerve to arterioles and pre-capillary sphincters
6. Of skeletal muscles and skin for vasodilation
7. Of non-essential organs (liver/gut) for vasoconstriction

Question 2

Explain Starling’s Law of the Heart

Answer 2

Increase in SV during exercise
Cause by:
1. Increase venous return
2. Greater diastolic filling
3. Cardiac muscle is stretched
4. Ventricles contract with more force
5. Ejection fraction increases

Question 3

When does blood pooling occur and what is it?

Answer 3

• Sudden stopping of exercise causes blood to pool in veins