Lipid Structure and Function

Question 1

Structural lipids characteristics

Answer 1

Lipids are insoluble in water and soluble in

nonpolar organic solvents.

Question 2

Phospholipids

• structure
• bonds

Answer 2

Amphipathic and form the bilayer of membranes.
Contain a hydrophilic (polar) head and hydrophobic
(nonpolar) tails. The head is attached by a
phosphodiester linkage, and determines the
function of the phospholipid

Question 3

Saturation

Answer 3

Saturation of the fatty acid tails determines the
fluidity of the membrane. Saturated fatty acid =
less fluid.

Single bonds means it is saturated

Question 4

Glycerophospholipids structure

Answer 4

Phospholipids that contain a glycerol backbone

Question 5

Sphingolipids structure and bonds

Answer 5

Contain a sphingosine backbone. Many (but not all)
sphingolipid are also phospholipids with a
phosphodiester bond. These are
sphingophospholipids.

Question 6

Sphingomyelins:

Answer 6

The major class of sphingophospholipids and
contain a phosphatidylcholine or
phohsphatidylethanolamine head group. Part of
the myelin sheath.

Question 7

Sphingomyelins

Answer 7

The major class of sphingophospholipids and
contain a phosphatidylcholine or
phohsphatidylethanolamine head group. Part of
the myelin sheath

Question 8

Glycosphingolipids

Answer 8

Attached to sugar moieties instead of a phosphate

group

Question 9

Glycosphingolipids - Cerebrosides

Answer 9

have 1 sugar connected to

sphingosine

Question 10

Glycosphingolipids Globosides

Answer 10

Have 2 or more sugars connected to sphingosine

Question 11

Gangliosides

Answer 11

Contain oligosaccharides with at least 1 terminal Nacetylneuraminic
acid (NANA).

Question 12

Waxes

Answer 12

Contain long-chain fatty acids esterified to longchain
alcohols. Used as protection against
evaporation and parasites in plants and animals.

Question 13

Terpenes

Answer 13

Odiferous steroid precursors made from isoprene. One
terpene unit (monoterpene) contains 2 isoprene units

Question 14

Terpenoids

Answer 14

Derived from terpenes via oxygenation or backbone

rearrangement. Odorous characteristics.

Question 15

Steroids

Answer 15

Contain 3 cyclohexane rings and 1 cyclopentane

Question 16

Steroid Hormones

Answer 16

Have high-affinity receptors, work at low
concentrations, and affect gene expression and
metabolism.

Question 17

Cholesterol

Answer 17

A steroid important to membrane fluidity and stability;

and serves as a precursor to many other molecules

Question 18

Prostaglandins:

Answer 18

Are autocrine and paracrine signaling molecules that
regulate cAMP levels. Affect smooth muscle
contraction, body temp, sleep-wake cycle, fever, pain

Question 19

Vitamin A:

Answer 19

Carotene, vision

Question 20

Vitamin D:

Answer 20

Cholecalciferol, bone formation.

Question 21

Vitamin E:

Answer 21

Tocopherols, antioxidants

Question 22

Vitamin K:

Answer 22

Phylloquinone & menaquinones. Forms

prothrombin, a clotting factor.

Question 23

Triacylglycerols:

Answer 23

Storage form of fatty acids. Contain 1 glycerol attached to
3 fatty acids by ester bonds. Very hydrophobic so do not
carry additional water weight.

Question 24

Adipocytes

Answer 24

Animal cells used specifically for storage of large

triacylglycerol deposits

Question 25

Free Fatty Acids

Answer 25

Unesterified fatty acids that travel in the bloodstream.

Salts of free fatty acids are soaps

Question 26

Saponification

Answer 26

The ester hydrolysis of triacylglycerols using a strong base

like sodium or KOH.

Question 27

Micelle

Answer 27

Can dissolve a lipid-soluble molecule in its fatty acid core,
and washes away with water because of its shell of
carboxylate head groups