Microcirculation, Fluid Exchange and the lymphatic system

Question 1

Each tissue controls it’s own blood flow relative to

Answer 1

needs of the tissue

Question 2

materials and fluid move across

Answer 2

the capillary wall

Question 3

flow of microcirculation

Answer 3

Nutrient artery - Arteriole à-“metarteriole” - pre-capillary sphincter - “true” capillary

Question 4

arterioles

Answer 4

highly muscular and diameter can change many fold

Question 5

metarterioles (terminal arterioles)

Answer 5

do not have a muscular coat, but have smooth muscle fibers that encircle the vessel at intermittent points.

Question 6

true capillary

Answer 6

originates from a metarteriole, a smooth muscle fiber that usually encircles the capillary (called precapillary sphincter)

Question 7

porosity for plasma proteins in capillaries walls, less to more porosity

Answer 7

Brain < Muscle < Intestine < Liver

Question 8

vasomotion

Answer 8

intermittent flow of blood through the capillaries

Question 9

What affects vasomotion ?

Answer 9

oxygen concentration

Question 10

The average function of the capillary system depends on

Answer 10

rate of blood flow through each tissue capillary bed
capillary pressure within the capillaries
transfer of substance between capillaries and surrounding interstitial fluid

Question 11

diffusion, which molecules cross the cell membrane and which ones are water soluble?

Answer 11

lipid-soluble substances (O2 and CO2) can diffuse directly through the cell membranes of capillaries without passing through the pores
water-soluble substances (water, sodium ions, chloride, and glucose) pass through the clefts (pores) of the membrane.

Question 12

Capillary pores in different tissues have different

Answer 12

permeability

Question 13

Net rate of diffusion of a substance through a membrane is proportional to the concentration difference between the two sides of the membrane if O2 is in greater concentration in capillary blood, where will it move?

Answer 13

out of capillary to tissue

Question 14

CO2 concentration is high in the tissue, where will it move?

Answer 14

CO2 moves into the capillaries to be carried away from the tissue.

Question 15

interstitial

Answer 15

spaces between cells

Question 16

fluid elements in interstitial fluid gel like

Answer 16

Hyaluronic acid
Water

Question 17

ficks law of diffusion

Answer 17

Solutes such as oxygen, carbon dioxide, glucose, electrolytes and fatty acids move by diffusion

Question 18

water moves by

Answer 18

osmosis

Question 19

water moves towards an area of

Answer 19

higher solute concentration