Structural Lipids

Question 1

What is an amphipathic molecule?

Answer 1

A molecule with BOTH a polar and nonpolar region.

Question 2

What is the difference between the bonding in saturated fatty acids and unsaturated fatty acids?

Answer 2

Saturated: contains single bonds

Unsaturated: contains one or more double bonds

Question 3

Are saturated fatty acids solids or oils at room temperature?

Answer 3

Solids because they have single bonds.

(The single bonds allows them to pack together tightly.)

Question 4

Are unsaturated fatty acids solids or oils at room temperature?

Answer 4

Oils because they have double bonds.

(The double bonds create kinks in their structure and prevents them from packing together tightly.)

Question 5

What are the four components of a phospholipid?

Answer 5

1. alcohol
2. phosphate group
3. backbone
4. fatty acid tails (2)

Question 6

What are the two types of phospholipids found in eukaryotic cells?

Answer 6

1. glycerophospholipids (glycerol backbone)
2. sphingolipids (sphingosine backbone)

Question 7

What is the only class of sphingolipids that are also phospholipids?

Answer 7

Sphingomyelins

Question 8

What are the three main subclasses of sphingolipids?

Answer 8

1. sphingomyelins
2. glycosphingolipids
   
   1. cerebrosides (1 sugar)
   2. globosides (2+ sugars)
3. gangliosides

Question 9

[Mnemonic]

Gangliosides are the “gangly” sphingolipids.

(how to differentiate gangliosides from other sphingolipids)

Answer 9

Gangliosides are the “gangly” sphingolipids.

Gangliosides have the most complex structure and functional groups (oligosaccharides and NANA) in all directions.

Question 10

What is the difference between a sphingolipid that is a phospholipid and one that is a glycolipid?

Answer 10

A sphingolipid that is a phospholipid: has a phosphodiester bond

A sphingolipid that is a glycolipid: has a glycosidic bond

Question 11

What is the function of waxes?

Answer 11

Membrane stability and waterproofing