Exchange and the lymphatic system

Question 1

How is the capillary structure specialised for exchange?

Answer 1

Lots of them
Thin-walled
Small diameter

Question 2

What are the 3 types of capillary structure?

Answer 2

Continuous
Fenestrated
Discontinuous

Question 3

Give an example of the capillaries with continuous structure?

Answer 3

Capillaries near the brain

Question 4

What are fenestrated capillaries used for?

Answer 4

Fluid exchange

Question 5

Give the 5 ways in which capillary endothelium prevents clots

Answer 5

Stops the blood from contacting the collagen
Produces Prostacyclin and nitrous oxide which inhibit platelet aggregation
Produces tissue factor pathway inhibitor (stops thrombin production)
Expresses thrombomodulin and heparin (Binds and inactivates thrombin)
Secretes tissue plasminogen activator

Question 6

How is the capillary to tissue diffusion self-regulating?

Answer 6

As the oxygen becomes used, the conc gradient increases and so more oxygen will diffuse in, the oxygen diffusing into the tissues goes down the concentration gradient

Question 7

What is the name of the pressure pushing fluid into the capillaries in bulk flow?

Answer 7

Osmotic pressure

Question 8

What is the difference between diffusion and bulk flow in capillaries?

Answer 8

Diffusion is where oxygen will move down the concentration gradient into the tissue from the capillary
Bulk flow is the movement of fluid in and out of the capillary

Question 9

Where is fluid lost in terms of bulk flow in the capillary?

Answer 9

The arteriole end