Cellular Processes [Cell Membrane]

Question 1

What do the hydrophobic regions of integral proteins consist of?

Answer 1

Non polar amino acids coiled into helices.

Question 2

What 3 things are allowed through the selectively permeable membrane?

Answer 2

Non polar uncharged (O2)
Lipid soluble (fatty acids)
Small uncharged polar (water, urea)

Question 3

What is the selectively permeable membrane impermeable to?

Answer 3

Large uncharged polar (glucose)

Ions

Question 4

What 5 things increase rate of diffusion?

Answer 4

Difference in conc.
High temp
Small 
Increase in SA
Small distances

Question 5

How can osmosis be prevented? What does it depend on?

Answer 5

Opposing force - hydrostatic (osmotic) pressure. Depends on number of particles in solution.

Question 6

What 3 things increase fluidity of the membrane?

Answer 6

Shorter lipid tail length
Double bonds
Less cholestrol

Question 7

What are peripheral?

Answer 7

Attached to inner or outer surface of cell membrane (cytoskeleton) and are easily removed by breaking ionic bonds with ion solution. They bend, change strength and hold other proteins in place.

Question 8

How much energy to cells use to maintain grandents?

Answer 8

30%

Question 9

Pd properties

Answer 9

Small
Mercury insensitive
Temp dependent