Hardman - Lipids

Question 1

Physical Property Trends of Fatty Acids

Answer 1

Non-polar, hydrophobic, 15% of human body, energy storage, membranes/vitamins/hormones

Question 2

Addition of Fatty Acids to Water =

Answer 2

Micelle = Fatty acid, lysophospholipids, detergents

Lipid Bilayer = Phospholipid, glycolipid

Liposome = Phospholipid, glycolipid

Question 3

Systemic Names of Fatty Acids

Answer 3

Saturated: Name of parent hydrocarbon w/oic for final “e”

Monosaturated: - enoic

Polyunsaturated: Two double bonds = dienoic, Three double bonds = trienoic

Cis/Trans: Cis/Trans- Δ#-fatty acid; # = carbons from head (Δ) end

cis-Δ9-octadecenoate = octadecenoic acid

Question 4

Omega Nomenclature

Answer 4

1. ## :0 or #n-
   1. Ex: 18:0 = 18 Carbon fatty acid w/no saturation
   2. Ex: 18:2n-6 = 18 Carbon fatty acid w/2 double bonds starting at 6 from the ω-end (tail)

Question 5

Fatty Acid Length trends?

Length Standard Groups

Answer 5

Length alters fluidity

Shorter = more fluid

(butter has longer chain than olive oil)

SCFA: < 6 carbons

MCFA: 6-12

LCFA: 13-21

VLCFA: >22

Question 6

Fatty Acid Saturation Trend

Answer 6

More saturation = more fluid

Addition of cis double bond decreases T_m (increases fluidity), looser packing due to double bonds

Question 7

Storage Lipids?

Answer 7

Triglycerols (Triglycerides) - TAGs

Question 8

TAGs

If saturated–where do double bonds present?

Answer 8

Structure: Simplest lipids from fats; non-polar/hydrophobic, provide stored energy, insulation, and cushioning

IF saturated, double bond will present on Carbon-2

Energy yield is 2x that of carbohydrates; unhydrated weigh less

Question 9

Membrane Lipids

Answer 9

Phospholipids, Glycolipids, Cholesterol

Question 10

Phospholipids

Answer 10

Form bilayers, ends are energetically unfavorable

Non-covalent interactions hold together, electrically polarized

Major components: Fatty acid, platform (glycerol, etc), phosphate, alcohol (choline, serine, etc)

Types: Lysophospholipids, plasmalogens, sphingolipids

Question 11

Lysophospholipids

Answer 11

Contain ony one acyl group–intermediate during metabolism or interconversion of phospholipids

Detergents

Question 12

Plasmalogens

Answer 12

Similar to phosphotidylcholine or ethanolamine

Ether-linked alkene

Signaling molecules

Question 13

Sphingolipids

Answer 13

Backbone is sphingosine instead of glycerol, includes sphingomyelins and glycoproteins

Question 14

Glycolipids

Answer 14

Structure: Sugar containing lipids NOT phospholipids in animals–derived from sphingosine

Amide Bond present at addition point for fatty acid unit

Question 15

Cholesterol

Answer 15

Structure: Flat, planar molecule

Makes membrane less fluid

Question 16

Eicosanoids

Answer 16

Enzymes

1. Prostaglandins (PGs)
2. Thromboxanes (TXs)
3. Leukotrienes (LTs)

Omega-6 (AA), Omega-3 (EPA)