18: Micro-circulation

Question 1

Average velocity of blood through capillaries dependent on

Answer 1

arteriole constriction
Venule pressure
Endothelial and local factors

Question 2

Diffusion of substances in blood

Answer 2

flow limited

increased flow= increased transfer

Question 3

Transcapillary efflux rate

Answer 3

= Flow x (arterial concentration - venous concentration)

Question 4

Factors driving fluid flitration

Answer 4

Hydrostatic pressure within capillary

Interstitial protein oncotic pressure

Question 5

Factors driving fluid reabsorption

Answer 5

interstitial fluid pressure (negligible unless edema)

Plasma protein oncotic pressure

Question 6

How does pressure change through the capillaries

Answer 6

Beginning: filtration
End: Reabsorption

Question 7

Purpose of lymph system

Answer 7

Maintain low interstitial hydrostatic and oncotic pressures
valves for unidirectional flow
Free flow of large molecules

Question 8

Increased arteriolar resistance

Answer 8

Increased reabsorption

Question 9

Increased venous resistance

Answer 9

increased filtration

Question 10

Size of junctions in the brain

Answer 10

Small

Question 11

Size of junctions in the liver

Answer 11

Large