Intro to Cellular Membranes

Question 1

Membranes are…

Answer 1

1. Composed of Lipids
2. Are bilayer
3. Consists of proteins (allows for penetrability)

Question 2

Phospholipid Bilayer

Answer 2

1.Polar Phosphate: Facing membrane surface (naturally negative)
Hydrophilic
2. Nonpolar Fatty Acid Tails: Facing the interior of the membrane
Hydrophobic

Amphipathic

Function: Prevent random movement of substance coming in and out of the cell.

Question 3

Fatty Acids

Answer 3

-Long unbranched chains
-Typically 14-20 carbons
-Form: Saturated or Unsaturated

Question 4

Saturated Fatty Acid

Answer 4

-Carbon is saturated with hydrogen
-Lacks double bonds

Question 5

Unsaturated Fatty Acid

Answer 5

-One or two double bonds
-Naturally are cis double bonds
-Creates kinks (bends) in fatty acid

Cis:
Natural Occurring
Most reactive
Creates more bend in the tail
Does not pact properly (easily breaks)

Trans:
More stable than cis

Question 6

Phosphoglycerides

Answer 6

All phospholipid
glycerol backbone, 2 fatty acid chains (1 of each kind), phosphate group, additional group