capillary soute and fluid exchange

Question 1

what are the four passive transport processes

Answer 1

diffusion
convection
osmosis
electrochemical flux

Question 2

where does solute and fluid exchange occur

Answer 2

capillaries

Question 3

what 4 factors control rate of solute transport

Answer 3

properties of passive diffusion
properties of solutes and membranes - fick’s law
properties of capillaries
permeability as a concept

Question 4

formula for time taken for passive transport to take place

Answer 4

t = x^2 /2D

Question 5

solute properties that affect transport

Answer 5

concentration gradient
solute size
lipid solubility of the solute

Question 6

membrane properties that affect passive transport

Answer 6

membrane thickness
membrane composition
aq pores in the membrane
carrier mediated transport
active transport mechanisms

Question 7

what does fick’s law describe

Answer 7

how much of a substance is transported per unit time

Question 8

eqn for Fick’s law

Answer 8

Js = -DA(ΔC/x)

Question 9

what are the three types of capillaries

Answer 9

continuous
fenestrated
discontinuous

Question 10

properties of continuous capillaries

Answer 10

moderate permeability - tight desmosomes, constant basement membrane

Question 11

where are continous capillaries found

Answer 11

BBB, muscle, skin, fat, connective tissue

Question 12

properties of fenestrated capillaries

Answer 12

high water permeability, modest disruption of membrane

Question 13

where are fenestrated capillaries foun

Answer 13

‘high water turnover’ tissues - salivary glands, kidney, synovial joints, ant eye, choroid plexus, gut mucosa

Question 14

properties of discontinuous capillaries

Answer 14

very large fenestrations, disrupted membrane

Question 15

where are discontinuous capillaries found

Answer 15

when cell movement is required - rbc’s in liver, spleen, bone marrow

Question 16

what three structural features of capillary walls can influence solute transfer

Answer 16

intracellular cleft
glycocalyx
caveola-vesicle system

Question 17

how big is the intracellular cleft

Answer 17

10-20nm wide

Question 18

what is the glycocalyx

Answer 18

-ve charged material, blocking solute permeation, access to transport mechanisms - highly regulated

Question 19

what are the caveolae and vesicles in the capillary wall

Answer 19

large system of pores

Question 20

what is permeability

Answer 20

rate of solute transfer by diffusion across unit area of membrane per unit concentration difference - how freely a solute crosses a membrane

Question 21

what is the eqn for Fick’s law modified for a porous membrane

Answer 21

Js = -P Am ΔC

where P = permeability - pore length, size, diffusion co
Am = SA of capillary involved in transport

Question 22

what are the main membrane transport mechanisms?

Answer 22

f

Question 23

how does the structure of capillaries change to regulate membrane transport?

Answer 23

f

Question 24

which properties of passive diffusion govern membrane transport

Answer 24

f

Question 25

what are the properties of solutes that govern membrane transport

Answer 25

f

Question 26

what are the properties of membranes that govern membrane transport

Answer 26

f

Question 27

define fick’s law

Answer 27

f

Question 28

define permeability

Answer 28

ff

Question 29

what controls diffusion rate and how and when does this occur

Answer 29

f