lipids

Question 1

describe the structure of fatty acids

Answer 1

consist of hydrophobic hydrocarbon chain with a teminal carboxyl group
-may be saturated or unsaturated

Question 2

cis configuration

Answer 2

the two hydrogen atoms adjacent to the double bond stick out on the same side of the chain

Question 3

saturated fatty acids

Answer 3

• carbon to carbon bonds are single
• no double bonds
• fully reduced/saturated with hydrogen atoms
• highly flexible due to free rotation around single bonds

Question 4

unsaturated fatty acids

Answer 4

• contain double bonds
• if 2 or more dbs- db is spaced at 3 carbon intervals
• position of db is speicfied by distance from carboxyl end

-

Question 5

polyunsaturated fatty acids

Answer 5

more than one double bond

Question 6

omega refers to….

Answer 6

the position of the double bond from the omega end of the FA

Question 7

omega 3 refers to

Answer 7

the position of the final double bond which is three carbons from the omega end of the fa chain

Question 8

omega 6 refers to

Answer 8

the position of the final double bond which is 6 carbons from the omega end of the fa chain

Question 9

characteristics of prostaglandins

Answer 9

• derived from eicosanoids (pufa with 20 carbons)
• synthesised from arachidonic acid via COX
• potent
• short half life
• multiple roles- infkammatory, platelet homeostasis

Question 10

characteristics of leukotreines

Answer 10

-eicosanoid family
-synthesised from arachidonic acid via LOX
-longer half life (up to 4 hrs)
-inflammatory
neutrophil adhesion

Question 11

name two lipids not containing glycerol

Answer 11

steroids and sphingolipids

Question 12

classify lipids containing glycerol

Answer 12

mono, di and tri acyylglycerol (triglycerides) (neutral)

phospholipids (charged)

Question 13

name two types of fatty acid derivatives

Answer 13

prostaglandins and leukotreines

Question 14

lipid functions

Answer 14

energy reserve
structural component of cells and organelles
involved in cellular signalling events (prostaglandins, leukotreins and steroids)

Question 15

structure of triglycerides

Answer 15

glycerol and 3 fatty acids

Question 16

function of triglycerides

Answer 16

principal storage form of energy in the body

found in adipose tissue

Question 17

DAG (diacylglycerol)

Answer 17

mobilisation of calcium

potent intracellular signaller

Question 18

monoacylglycerol

Answer 18

breakdown product of TAG

Question 19

sphingolipids

Answer 19

sphingosine + r group + fatty acid

Question 20

functions of FAs

Answer 20

1. structural component of membrane lipids
2. attached to proteins to enhance their ability to associate with membranes
3. precusors of hormones
4. alterations in fa metabolism linked to obesity and diabetes
5. exist free in the body
6. can be oxidised to provide energy

Question 21

cholesterol

Answer 21

essential biomolecules
metabolic precursor of- vit d, bile acid, steroid hormones
key role in structure of membranes
needed in coinstant supply

Question 22

describe structure of steroids

Answer 22

contain characteristic fused ring structure with hydroxyl or keto group of carbon 3

Question 23

name 2 essential fatty acids

Answer 23

linoleic acid and alphalinolenic acid

Question 24

linoleic acid is

Answer 24

an omega 6 essential fatty acid

Question 25

alpha linolenic acid is

Answer 25

an omega 3 fatty acid