MASS TRANSPORT IN HUMANS

Question 1

Tissue fluid formation & return

Answer 1

1. High hydrostatic pressures forces fluid out
   2.large porteins remain in capillary
2. Lowers the water potential in capillary
3. Water enters calillary via osmosis
4. Excess water is removed from tissues via lymph vessels

Question 2

Mass flow definition

Answer 2

Mass flow in the bulk movement of liquids due to pressure difference

Question 3

Cardiac output equation

Answer 3

CO = stroke volume x heart rate

Question 4

Improtance of heart valves

Answer 4

Prevents backflow

Question 5

Blood flow through heart

Answer 5

Heart —> lungs —> heart —> tissues —> heart

Question 6

Pressure in chambers

Answer 6

1. Blood volume increases pressure in atrium
2. Pressure in atrium greater than in ventricle
   3 atriventicular valves open
3. Blood volume increases pressure in ventricle
4. Pressure in ventricle greater than in atrium
5. Atriventicular valve closes
6. Pressure in ventricles is greater than in aorta
7. Semi lunar valves open
8. Pressure in aorta is greater than in ventricle
9. Semi lunar valve closes

Question 7

Risk factor in coromary heart disease

Answer 7

High cholesterol diet + high lipid diet + lack of excersice + smoking = high blood pressure + increases blood toxins + increases cholesterol level = damage to endothelium wall

Question 8

Capillaries

Answer 8

Only has endotheical layer
Small diameter so creates friction this reduces blood pressures

Question 9

Arterioles

Answer 9

Eslastic layer is thinner
Muscle layer is thicker
Causes fall in blood pressure as greater frictiom between blood and vessel wall

Question 10

Artery

Answer 10

Outer layer = goves support and stregth to wall
Endothelial layer = one cell thick and its a smooth layer so reduces friction
Elastic layer = streches and recoils to maintain a hydrostatic pressure on the blood