Fatty Acids
Fatty Acid Nomenclature
Omega-3 Fatty Acids
Sphingolipid Recap
Steroid Hormones
Lipid Vitamins
Comprehensive Final Map
Biological Membranes
Physical Properties of Biological Membranes
Types of Membrane Proteins
Integral Membrane Proteins
Peripheral Membrane Proteins
Lipid-Linked Membrane Proteins

Practice: Which fatty acid chain would you expect to be least soluble in water?

a) 16-Carbon fatty acid. 

b) 4-Carbon fatty acid.

c) 22-Carbon fatty acid.

d) 12-Carbon fatty acid.

Concept #2: Saturated vs. Unsaturated Fatty Acids

Practice: What is the molecular formula of Linolenic acid, an 18-carbon polyunsaturated fatty acid with 3 double bonds?

a) C18H32O2

b) C18H30O2

c) C28H30O2


Concept #3: Melting Point of Fatty Acids

Practice: What aspect of each of the 18-carbon fatty acids in the table below is correlated with their melting point?

a) The charge of the carboxylic acid group.

b) The length of the hydrocarbon chain

c) The number of double bonds

d)The polar hydrocarbon chains

Practice: What happens to the melting point in fatty acids as the hydrocarbon length increases?

a) It increases.  

b) It decreases.

c) It stays the same.

d) There is no direct correlation.

Practice: Unsaturated fatty acids: 

a) Usually contain a double bond with cis stereochemistry.

b) Are found in both plants and animals. 

c) Sometimes contain multiple double bonds. 

d) Have lower melting points than the analogous saturated fatty acids.

e) All of the above are correct.

Practice: Compared to unsaturated fatty acids, saturated fatty acids have:

a) Longer carbon chains. 

b) Shorter carbon chains. 

c) More double bonds. 

d) Lower melting points.

e) Looser packing of their hydrocarbon chains.

f) Tighter packing of their hydrocarbon chains.

Practice: Which of the following are correct with regard to saturated fatty acids?

a) They are generally solid at room temperature. 

b) The carbon backbone contains at least one double bond, creating a kink in the chain. 

c) Come primarily from vegetable products. 

d) They are only hydrocarbon chains, making them liquids at room temperature.

e) Cannot be present in other lipids, such as phospholipids.

Practice: Match each of the fatty acids with the appropriate melting point:

a) CH3(CH2)18COOH ______

b) CH3(CH2)14COOH ______

c) CH3(CH2)10COOH ______

d) CH3(CH2)7CH=CH(CH2)7COOH ______

e) CH3(CH2)4CH=CH-CH2-CH=CH(CH2)7COOH ______