Venous return and blood redistribution

Question 1

what is the sympathetic nervous system?

Answer 1

is controlled by the CARDIAC CONTROL CENTRE (CCC) found in the MEDULLA OBLONGATA. It sends signals via sympathetic nerves and is responsible for increasing heart rate.

Question 2

what is venous return

Answer 2

the volume of blood that returns to the right side of the heart via ventricles and veins

Question 3

what is Starling’s Law

Answer 3

increase in venous return
=
increase in stroke volume
=
increase cardiac output

Question 4

what is vascular shunt mechanism

Answer 4

redistribution of blood using network of blood vessels to control where the blood in the body goes

Question 5

5 mechanisms of venous return

Answer 5

1) pocket values
2) muscle pump
3) respiratory pump
4) smooth muscle
5) gravity

Question 6

what do pocket valvules do?

Answer 6

prevent back flow of blood and direct it towards the heart

Question 7

what is vasometer control centre (VCC)

Answer 7

controls blood redistribution
is located in the MEDULLA OBLONGATA.

Question 8

what is pre-capillary sphincters?

Answer 8

little muscles rings at the end of arterioles
- vasodilation
- vasoconstriction

Question 9

what is vasodilation?

Answer 9

allows blood flow

Question 10

what is vasoconstriction?

Answer 10

prevents/restricts blood flow

Question 11

why do baroreceptors detect?

Answer 11

the increase in blood pressure

Question 12

what do chemoreceptors detect?

Answer 12

• an increase in CO2 and lactic acid
• a decrease in in O2 and blood pH