lipids

Question 1

how do you classify a lipid?

Answer 1

molecules which are soluble in organic solvents and insoluble in water
they form aggregates held together by weak interactions

Question 2

what are the 4 functions of lipids?

Answer 2

structural component of membrane
intracellular storage depots of metabolic fuel
protection

Question 3

what are the simplest lipids?

Answer 3

fatty acids

Question 4

which end do you start numbering the carbons in a fatty acid?

Answer 4

from the carboxyl group end

Question 5

what are examples of saturated fatty acids?

Answer 5

palmitic acid

stearic acid

Question 6

what is an example of an unsaturated fatty acid?

Answer 6

oleic acid

Question 7

what is the relationship between chain length and melting point?

Answer 7

as the chain lengthens, the melting point increases

Question 8

how many isomeric forms can molecules that contain double bonds occur in?

Answer 8

two

Question 9

what two isomeric forms can molecules containing double bonds occur in?

Answer 9

cis

trans

Question 10

what are cis isomers?

Answer 10

similar groups are on the same side of the double bond

Question 11

what are trans isomers?

Answer 11

similar groups are on opposite sides of the double bond

Question 12

what does amphipathic mean?

Answer 12

part of the molecule is hydrophobic and part is hydrophilic

Question 13

what is the relationship between the number of double bonds and the degree of curve of the chain?

Answer 13

the more double bonds the more curve

Question 14

what angle does a double bond create in a chain?

Answer 14

30 degree

Question 15

what is an acylglycerol?

Answer 15

esters of fatty acids with a sugar alcohol called glycerol derived from glyceraldehyde

Question 16

what is a triacylglycerol?

Answer 16

an acylglycerol with 3 fatty acids

Question 17

what is a diacylglycerol?

Answer 17

an acylglycerol with 2 fatty acids

Question 18

what is a monoacylglycerol?

Answer 18

an acylglycerol with one fatty acid

Question 19

what is the function of triacylglycerols?

Answer 19

storage of metabolic fuels

Question 20

are triacyglycerols amphipathic?

Answer 20

no

Question 21

how are fatty acids broken down?

Answer 21

beta oxidation

Question 22

what makes triacylglycerols good for storage?

Answer 22

uncharged
neutral
compact

Question 23

what are adipocytes?

Answer 23

fat storage cells

Question 24

what is hydrogenation?

Answer 24

an industrial process which saturates the double bonds in an oil and solidifies it using hydrogen and a catalyst

Question 25

what is liquefaction?

Answer 25

the opposite of hydrogenation | when hard fats are exposed to air and are oxidised and double bonds are formed

Question 26

what are waxes?

Answer 26

similar to triacylglycerols but they are esters of long chain fatty acids with long chain monohydroxylic alcohols

Question 27

what is the function of waxes?

Answer 27

external protection

Question 28

what are phospholipids?

Answer 28

more complex lipids similar to acyclycerols but have a hydrophilic phosphate and alcohol group

Question 29

are phospholipids amphipathic?

Answer 29

yes

Question 30

what is the most abundant phospholipid in animal tissue?

Answer 30

phosphatidylcholine

Question 31

what is the parent compound of sphingolipids?

Answer 31

nitrogenous base

Question 32

what is a sphingosine?

Answer 32

a long chain amino alcohol

Question 33

what is a ceramide?

Answer 33

a sphingosine joined to a fatty acid | has two long hydrocarbon tails

Question 34

what are the three different subclasses of sphingolipids?

Answer 34

sphingomyelins cerebrosides gangliosides

Question 35

where are sphingomyelins present?

Answer 35

in membranes | especially myelin sheaths

Question 36

what are cerebrosides?

Answer 36

a sphingolipid and a glycolipid

Question 37

where are gangliosides found?

Answer 37

in cell surface membranes such as in the grey matter of brain tissue

Question 38

what is tay sachs disease?

Answer 38

an inherited condition which impairs the function of the lysosomal enzyme beta HEXA

Question 39

what is the result of the beta HEXA enzyme being impaired?

Answer 39

prevents the breakdown of GM2 ganglioside | it then accumulates to toxic levels which can cause neuron destruction

Question 40

what does tay sachs disease cause?

Answer 40

retarded development paralysis blindness death by the age of 3 or 4

Question 41

what are isoprenoids?

Answer 41

a class of hydrocarbons which are composed of repeats of the 5 carbon isoprene unit

Question 42

what are eicosanoids derived from?

Answer 42

arachidonic acid

Question 43

what is the role of prostaglandins?

Answer 43

local hormones involved in promoting inflammation

Question 44

what do thromboxanes regulate?

Answer 44

smooth muscle contraction and nerve transmission