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Flashcards in Membrane Transport Deck (23):
1

What are the types of gradients?

  • Pressure gradients
  • Electrical gradients
  • Concentration gradients

2

Define Fick's Law of Diffusion

Gradient = (Concentration difference)(x-area)(temp)

/ (distance)(MW)

3

A scientific law is

an identifiable repetitive behavior in nature which always occurs

4

A scientific theory is

an explanation of how or why something (like a law) always occurs

5

According to Fick's law, diffusion rate has a direct relationship with

  • concentration difference
  • area
  • temp

6

According to Fick's law, rate of diffusion has an indirect relationship with

  • distance
  • molecular weight

7

Diffusion is

  • a type of passive transport
  • caused by random movemment of particles of fluid, gas or particles

8

Net diffusion is

  • Passive transport
  • measurable random movement of particles of fluid, gas or particles

9

Osmosis is

the diffusion of a solvent through a membrane from an area of low solute concentration to an area of high solute concentration

10

When no channel is involved, transport of a solute across a membrane is fastest when 

the molecule is small, lipid soluble and carries no charge

11

When a channel is involved, diffusion through a membrane is fastest when 

  • the molecule is small, carries a positive charge

or

  • the molecule is small and is non-polar

12

Diffusion is _____ related to lipid solubility

  • directly
  • Increased lipid solubility = increased permeability

 

13

Diffusion is ______ related to molecular size

  • inversely
  • Increased molecular size = decreased permeability

14

Diffusion is ______ related to electrical charge

  • directly
  • postive charge = increased permeability (rate)

15

Dialysis is the

net movement of a solute through a membrane

16

Hemodialysis is the

removal of excess urea and K+ by dialysis of the blood

17

The characteristics of carriers are

  • They are membrane-bound proteins (integral)
  • They are highly specific to the solute(s) that they carry 
  • Maximum transport rates is reached when all attachment sites are full
    • faster than channel transport but has a max threshold
  • Transport can be blocked by inhibitors

18

The characteristics of Fascilitated diffusion are

  • Requires a carrier
  • Does not require ATP
  • Faster than non-carrier diffusion
  • Maximum transport rate when all binding sites are full

19

The action of a symport is

to move 2 molecules in the same direction (by one carrier)

20

The action of an antiport is

to move 2 different molecules in opposite directions (by one carrier)

21

Processes of endocytosis include

phagocytosis (eating) and pinocytosis (drinking)

22

Processes of exocytosis are

secretion (hormones, sweat, enzymes, etc.)

and excretion (waste)

23

Remember Na+ ___, K+ ___.

Na+ in, K+ out

Na+ in, K+ out

Na+ in, K+ out

Na+ in, K+ out

Na+ in, K+ out

Na+ in, K+ out

Na+ in, K+ out