Structure And Function Of Lipids

Question 1

What is the primary function of lipids?

Answer 1

they provide energy and store energy, as well as, forming cell membranes

Question 2

What is the difference between a simple lipid and a complex lipid?

Answer 2

A complex lipid has a non-lipid component upon which is it based.

Question 3

Fatty Acids

Answer 3

Components of lipids, derived by hydrolysis of simple and complex lipids

Question 4

what are the components of a fatty acid?

Answer 4

Simple hydrocarbon chain, with methyl group on one end and a carboxyl end on the other.

Question 5

what are the two types of fatty acids and what is that classification based on?

Answer 5

Saturated and unsaturated fatty acids. Saturated have no double bonds and unsaturated have a double bond.

Question 6

what are the most abundant fatty acids in humans?

Answer 6

Palmitate and stearic acid

Question 7

What configuration is the double bond of most natural fatty acids in?

Answer 7

Cis- resulting in a kink

Question 8

How does the number of double bonds correlate to the melting temperature?

Answer 8

More double bonds=lower melting point (because they can’t stack)

Question 9

omega-6 fatty acids

Answer 9

Essential fatty acid (linoleic acid), that has the double bond on the omega carbon.

Question 10

From which end does the omega counting system begin?

Answer 10

The methyl end

Question 11

What is aracidonic acid a precursor for?

Answer 11

pro inflammatory eicosanoids

Question 12

Omega 3 fatty acid

Answer 12

essential amino acid (alpha-linolenic acid) where the first double bond is one the 3 carbon from the methyl side.

Question 13

Why are linoleic and linolenic consider essential fatty acids?

Answer 13

Humans cannot add a double bond after C-9 in a fatty acid

Question 14

What are trans fatty acids?

Answer 14

The double bond is in the trans conformation, meaning that they are almost linear and there is no “kink”. So they behave like saturated fatty acids with limited mobility.

Question 15

Triacylglycerol

Answer 15

Glycerol (alcohol) backbone with 3 fatty acids. Hydrophobic (simple lipid) and storage form of the lipids.

Question 16

What are the two types of phospholipids?

Answer 16

Glycerophospholipids and sphingophospholipids.

Question 17

What is the general structure of a glycerophospholipid?

Answer 17

Glycerol with a saturated fatty acid, unsaturated fatty acids, and phosphate-nitrogen containing base.

Question 18

What is the role of phospholipid in surfactant?

Answer 18

DPPC (dipalmitoylphosphatidylcholine) is a component of surfactant that helps to increase surface tension of the alveolar fluid and keep the alveolus from collapsing.

Question 19

Describe sphingophospholipids

Answer 19

contains the amino alcohol sphingostine, one fatty acid, and phosphate with choline. Helps to form the myelin sheath.

Question 20

glycolipids

Answer 20

Sphingostine backbone, with a fatty acid and carbohydrate. Typically found in the outer leaflet and help to form the myelin sheath.