Diffusion

Question 1

Permeability of membranes include

Answer 1

Permeable of water and other small molecules

Forms a selective barrier

Question 2

Diffusion elements

Answer 2

Water
Oxygen
Carbon dioxide
Small/non-polar/ lipid soluble as they are able to dissolve across the phospholipid membrane.

Question 3

Rate of diffusion is affected by (6)

Answer 3

Concentration gradient

Surface area

Diffusion pathway distance

Temperature

Lipid solubility

Molecule size

Question 4

What is fick’s law

Answer 4

Rate of diffusion is directly proportional to

(Conc grad. X SA)/ diff dist.

Question 5

What cannot pass through the phospholipid barrier directly

Answer 5

Water soluble, polar/ionic molecules

THEY USE FACILITATED DIFFUSION

Question 6

What is a limiting factor in facilitated diffusion

Answer 6

The amount of protein carriers. (They are specific for each molecule.)

Question 7

Code transport

Answer 7

A type of facilitated diffusion that brings molecules and ions into cells together of the same transport protein.

Question 8

Describe an example of code transport

Answer 8

Glucose and sodium attach to carrier protein

Carrier protein changes shape

Glucose and sodium diffuse separately across the cell

Glucose passes into blood by facilitated diffusion and sodium by active transport.

Question 9

What types of molecules use facilitated diffusion

Answer 9

Water soluble molecules

Polar molecules

Question 10

Define diffusion

Answer 10

The net movement of particles down a concentration gradient from a higher to lower concentration until an equilibrium is reached.