lipids

Question 1

what are some functions of lipids

Answer 1

membrane structure, cofactors for enzymes (coenzyme Q for ATP synth in mitochondria)
pigments
antioxidants- vit e

Question 2

what are the two major categories based on structure and function of lipids

Answer 2

lipids that have fatty acids (storage lipids and membrane lipids)
lipids that do not have fatty acids (cholesterol, vitamins, pigments)

Question 3

what unsaturated fats are good for you

Answer 3

poly + monounsaturated

Question 3

give example of polyunsaturated fats

Answer 3

sunflower oil, cold water fish

Question 4

give examples of monounsaturated fats

Answer 4

olive oil, nuts

Question 5

are natural fatty acids branched or unbranched

Answer 5

typically unbranched with even number of carbons

Question 6

define saturated, monounsaturated, and polyunsaturated

Answer 6

saturated= no double bonds
monounsaturated=one double bond between carbons in alkyl chain
polyunsaturated=more than one double bond in alkyl chain

Question 7

what does 18:1 delta 9 mean

Answer 7

describes the location of the first carbon in relation to the functional group. the 18 stands for number of carbons in main chain, the 1 stands for the number of double bonds. the 9 means the carbon at which the double bond arises.

Question 8

how does omega nomenclature differ from delta

Answer 8

describes the loaction of first carbon from the terminal methyl (opposite end to functional group) and ONLY shows the location of the first double bond

Question 9

where can you find omega 6 + what is function

Answer 9

meat + eggs, pro inflammatory

Question 10

sources and function of omega 3

Answer 10

minimally inflammatory, inflammation resolving. fish

Question 11

what is the relationship between solubility and chain length

Answer 11

solubility decreases as chain length increases

Question 12

what is relationship between melting poiny and chain length

Answer 12

decreases as the chain length decreases and as the number of double bonds increase

Question 13

what is rhe cause of kinks in fatty acid chains

Answer 13

double bonds in cis configuration- common in natural unsaturatied fatty acids

Question 14

which fatty acids can pack togehter in an orderly way

Answer 14

saturated fatty acids - unsaturated have kinks so pack worse

Question 15

does saturated fat or unsaturated fats melt quicker

Answer 15

unsaturated as it takes less thermal energy to disrupt the packings of them

Question 16

write a note on trans fatty acids

Answer 16

form by partial dehydrogenation of unsaturated fatty acids (increases shelf life)

the trans double bond results in an extended conformation meaning they can pack more and in turn have higher melting points.

can be a risk of developing cardiovascular disease.

Question 17

what are triglycerides

Answer 17

lipid with three fatty aicds with glycerol backbone.

Question 18

why can FAs carru more water

Answer 18

they are non polar

Question 19

why can FAs carry more energu

Answer 19

they are more reduced

Question 20

what are waxes

Answer 20

esters of long chained saturated/unsaturated with long chain alcohols. insoluble and high melting point

Question 21

fucntions of waxes

Answer 21

waterproofings for bird feathers, use in lotions ointments and polishes

Question 22

what are the three types of membrane lipids

Answer 22

glycerophospholipid, glycolipid, sterol

Question 23

what are glycerophospholipids

Answer 23

primary constituents of cell membranes

two fatty acids form ester bonds with the first and second hydroxyl groups of L-glycerol-3-phosphate

Question 24

is the phosphate group in glycerophospholipids polar or non-polar

Answer 24

polar + charged

Question 25

what can sometimes happed to the phosphate group

Answer 25

further esterified by an alchohol resulting in the attachment of a head group

Question 26

what is another name for glycerophospholipids

Answer 26

phosphoglyceride

Question 27

what is phosphatidylcholine

Answer 27

major componenet of eukaryotic cell membranes

Question 28

what is phosphatidyl serine

Answer 28

• indicator (biomarker) of apoptosis

Question 29

what is a sphingolipid

Answer 29

has a backbone not of glycerol but of an amino alcohol called sphingosine where a fatty acid is joined to sphingosine via amide links rather than ester

Question 30

what relation have glycospinolipids have to blood groups

Answer 30

blood groups are partially determined by the type of sugars in the head groups of glycosphingolipids

Question 31

what determines the structure of sugar in a blood group

Answer 31

glycosyltransferases

Question 32

what does the glycosyltransferase transfer for an A blood group

Answer 32

n acetylgalactosamine

Question 33

what does glycosyltransferase transfeer for b blood group

Answer 33

galactose

Question 34

what is the general structure of a sterol

Answer 34

steroid nucleus with 4 fused rings. presence of a hydroxyl group (polar head) in the A ring. can have various nonpolar side chains

Question 35

what are some roles + sources of cholesterol

Answer 35

cholesterol- thicken plasma membrane, moderate permeability in membrane

sourced from food or synthesised in liver

Question 36

how does cholesterol move through the body

Answer 36

bound to proteins + is transported to tissues by blood vessels

Question 37

what are ether lipids

Answer 37

common in vertebrate heart tissue, is a vinyl ether analog of phosphatidylethanolamine i.e plasmalogen

Question 38

what are the functions/features of ether lipids

Answer 38

function is not well understood. they are resistant to cleavage by common lipases but are cleaved by particular specific lipases. could be increasing membrane rigidity, source of signaling lipds, or antioxidant.

Question 39

how are phospholipids degraded

Answer 39

by phospholipases A-D where eac enzyme cleaves a specific bond

this takes place in the lysosome

Question 40

how are gangliosides are degraded

Answer 40

via enzymatic cleavages where a dysfunction of the breakdown can result in buildup of gangliosides categorised as a lysosomal storage disorder

Question 41

what sort of diseases can be caused by ganglioside recycling dysfunction

Answer 41

gauchers disease, generalised gangliosidosis

Question 42

what are polyketides

Answer 42

compounds synthesised similarly to fatty acid biosynthesis. commonly used as medicine i.e lovastatin which blocks cholesterol synthesis via enzyme blockage.