Lipids

Question 1

Describe the structure of triaglycerols

Answer 1

glycerol and 3 fatty acid chains

Question 2

Describe the structure of glycerophospholipids

Answer 2

glycerol and 2 fatty acid chains and 1 chain of PO4+alcohol

Question 3

Describe the structure of phospholipid sphingolipids

Answer 3

sphingosine and 1 fatty acid chain and 1 chain of PO4+choline

Question 4

Describe the structure of glycolipid sphingolipids

Answer 4

sphingosine and 1 fatty acid chain and 1 chain of mono-oroligosaccharide

Question 5

Describe the structure of stearic acid

Answer 5

octadecanoic acid (18:0)

Question 6

Describe the structure of palmitic acid

Answer 6

hexadecenoic acid (16:0)

Question 7

Describe the structure of oleic acid

Answer 7

octadecanoic acid (18:1(n-9))

Question 8

Describe the structure of alpha linolenic acid

Answer 8

octadecatrienoic acid 18:3(n-3)
double bonds at 9, 12, 15

Question 9

Describe the structure of linoleic acid

Answer 9

octadecadienoic acid 18:2(n-6)
double bonds at 9, 12

Question 10

Describe the structure of arachidonic acid

Answer 10

eicosatetraenoic acid 20:4(n-6)
double bonds at 5, 8, 11, 14

Question 11

List the functions of triaglycerols

Answer 11

• nonpolar
• variable FAs on each glycerol
• mostly saturated –> solids at room temp
• mostly unsaturated –> liquids at room temp

Question 12

Describe the naming of simple TAGs

Answer 12

3 stearic acid chains –> tristearoglycerol

3 oleic acid residues –> trioleoglycerol

Question 13

Describe some functions of TAGs

Answer 13

• insulation
• protection store energy
• more energy efficient than carbohydrates

Question 14

List some features of phosphoglycerides

Answer 14

• 3rd position point on glycerol occupied by a phosphate
• amphiphilic –> contain hydrophilic and hydrophobic parts

Question 15

List 4 common head groups on phosphoglycerides

Answer 15

serine
choline
inositol
ethanolamine

Question 16

What are sphingolipids?

Answer 16

• membrane lipids
• FA via amino group forms a ceramide

Question 17

What is sphingomyelin?

Answer 17

• contains phosphorylcholine
• usually 2 straight chains
• alters fluidity and gives tighter packing
• myelin sheath

Question 18

What are the features of glycolipids?

Answer 18

• amphipathic
• act as recognition molecules

Question 19

Describe the structure of steroids

Answer 19

• relatively non-polar
• 4 fused rings

Question 20

Describe the features of cholesterol

Answer 20

• amphipathic
• rigid and flat structure
• increases rigidity at high temps
• increases fluidity at low temps by preventing fatty acid association

Question 21

What is simvastatin?

Answer 21

• lipid-lowering
• reduces amount of cholesterol made by the liver

Question 22

What is cholesterol a precursor for?

Answer 22

• sex hormones
• glucocorticoids
• mineralcorticoids
• vitamin D
• bile salts

Question 23

What are terpenoids?

Answer 23

• synthesised from isoprenoids
• precursor for vitamin A, vitamin K, ubiquinone