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Biochemistry > Lipid Metabolism L16 L17 > Flashcards

Lipid Metabolism L16 L17 Flashcards

1
Q

what is a lipid

A

chemically diverse group of compounds which are not soluble in water but soluble in non-polar organic solvents – contain

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2
Q

how are lipids usually related to fatty acids

A

they contain fatty acids or they are made from fatty acids

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3
Q

is cholestrol a lipid

A

Cholestrol is a sterol, but many regard it as a lipid and does not contain fatty acid but can attach to a fatty acid

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4
Q

problem of lipid transport around the body

A

not soluble in water – problem when transporting around the body in blood, plasma of the blood is water based so lipids wont dissolve in it

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5
Q

what is a fatty acid

A

long hydrocarbon chain (containing carbon & hydrogen) with a terminal carboxyl (COOH) group

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6
Q

what is the general formula of a fatty acid

A

CH3(CH2)nCOOH

n is a variable number

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7
Q

how many carbons do fatty acids in plants and humans have

A

even number of carbons

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8
Q

how many carbons do fatty acids in bacteria usually have

A

Uneven usually produced by bacteria

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9
Q

why can we sometimes have uneven number carbon fatty acids

A

we can ingest bacteria, these an end up in our tissues (animals don’t make them)

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10
Q

what forms of fatty acids are there in the body

A 
triacylglycerol
phospholipids
free fatty acids
glycolipids
cholesterol ester
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11
Q

what is triacylglycerol

A

fat

adipose tissue

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12
Q

what is the biggest amount of lipid in the body

A

triacylglycerol

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13
Q

what is adipose tissue importance

A

biggest store of energy, cant survive without it

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14
Q

what are phospholipids

A

major component of all membranes

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15
Q

what do the most abundant phospholipids in the body contain

A

have a glycerol backbone, have two fatty acids attached to them and on third carbon of glycerol is phosphate and alcohol group

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16
Q

what are free fatty acids

A

Non-Esterified fatty acids (NEFA) not attached to anything

plasma

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17
Q

what are glycolipids

A

carbohydrate and lipid

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18
Q

what is cholesterol ester

A

cholesterol with fatty acid attached to it, storage form

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19
Q

what is the fatty acid level like in the blood when we awake before eating

A

before eating when wake up will be high level
When not eating and asleep, no stimulation to produce insulin, fat tissue starts to break down some reserves and break down some triglycerol release non-esterified fatty acids

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20
Q

what happens to the fatty acid level in the blood when we consume food after sleeping

A

after eaten will lower due to regulation of fatty acid release due to insulin
soon as eat insulin rises, turn off enzyme e which breaks down the fat and levels of fatty acid go down

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21
Q

what are the major biological roles of fatty acids

A

energy storage and production
protection/insulation
biological membranes
precursors of other bioactive molecules

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22
Q

why is it important to have energy storage and production

A

if couldn’t do this our meals would have to match our requirements exactly – would have to graze all day release excess stored energy

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23
Q

what provides protection and insulation - fatty acids

A

triacylglycerol

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24
Q

what is the importance of phospholipids in membranes

A

isolate cell/organelles from outside environment
allow communication with outside environment (not completely sealed)
protect from outside, keep certain molecules in and others out

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25
Q

what bioactive molecules are fatty acids precursors of

A

eicosanoids

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26
Q

what are examples of eicosanoids

A

prostaglandins
prostacyclins
thromboxanes
leukotrienes

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27
Q

what are eicosanoids

A

all are local hormones, immediate effect on cell itself or cells surrounding it

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28
Q

what is the structure of triacylglycerols

A

Esters of 3 Fatty Acids with glycerol backbone

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29
Q

what is the structure of phospholipids

A

Esters of 2 Fatty acid with glycerol backbone

3rd carbon of glycerol attached to a phosphate group + another alcohol (often containing nitrogen)

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30
Q

what are the three fatty acids like that are attached to the triacylglycerol

A

Rare for the three fatty acids to be the same only usually happens if artificially manufactured triacyglycerols for any reason they want to have it completely homogenous

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31
Q

what is triacylglycerol like at room temperature

A

Triacyglycerol that was a long chain of saturated fatty acids very solid at room temp

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32
Q

what are unsaturated fatty acids like at room temperature

A

Unsaturated fatty acids are flexible at room temperature – give membranes flexibility (when talking about phospholipids too)

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33
Q

how can fatty acids differ

A 
chain length
number of double bonds
* none = saturated
* 1 = monounsaturated
* >1  = polyunsaturated
position on the chain of the double bonds
type of double bonds (cis and trans)
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34
Q

how many carbons do most fatty acids have

A

16-18

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35
Q

what double bond if mainly found in nature

A

cis

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36
Q

what double bond is mainly found in bacteria

A

trans

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37
Q

why would we sometimes have trans double bond fatty acids in our body

A

if we ingest bacteria with them

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38
Q

what is a cis double bond

A

carbons both on the same side

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39
Q

what is a trans double bond

A

carbons on opposite sides

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40
Q

how can trans double bonds be formed

A

Can get trans fatty acids by chemically hydrogenating fat

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41
Q

why is a cis bond fatty acids fluid at room temperature

A

Cis bond put bend in the fatty acid, so fluid at room temp

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42
Q

why is a trans bond fatty acid solid at room temperature

A

Trans bond has a straight chain, behaves more like a fatty acid, solid at room temperature

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43
Q

what effect is there is a cis bond is changed to a trans bond

A

changes the nature and the biological properties

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44
Q

how can fatty acids be named

A 
- if start from carboxyl end 
name them based on the number of double bonds
carbon length
- if start from the methyl end
which omega family they're in
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45
Q

what does omega-x- denote in naming fatty acids

A

Omega-x- denotes the position of the first double bond from the orange end
methyl end

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46
Q

what does delta-x- denote in naming fatty acids

A

Delta-x- similar to systematic in that it describes the position of double bonds from the carboxyl end

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47
Q

which end should we name from in fatty acids if we want to put it into a ‘family’

A

methyl

will group into omega 3, 6, 9

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48
Q

what family would fatty acids from methyl end with first double bond from the third be in

A

omega 3

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49
Q

what are all polyunsaturated fats made from

A

monounsaturated fatty acids by further desaturations (more double bonds)

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50
Q

what fatty acids can can animals make

A

only major ones animals can make de novo are based on oleic acid

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51
Q

what effect do animals have on fatty acids

A

insert double bonds between existing bond and carboxyl group

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52
Q

where do we get linoleic acid and alpha-linolenic acids from

A

Plants can make both linoleic acid and alpha-linolenic acid we can consume these as we need them, we can change them when they’re in out body
can’t make linoleic acid or α-linolenic acid from oleic acid enzymes cant put the double bond the other side of the existing double bond, it has to be from the carboxyl end

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53
Q

what effect do plants do to fatty acids

A

insert double bonds between existing bond and methyl group

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54
Q

what are fatty acids important for

A

Play a vital role in membrane function

Are the precursors of eicosanoids

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55
Q

what are MUFA

A

mono unsaturated fatty acids

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56
Q

what are PUFA

A

poly unsaturated fatty acids

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57
Q

how does 2C acetyl CoA go to 3C

A

Acetyl CoA carboxylase enzyme adds another carbon onto acetyl CoA to make malonyl CoA

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58
Q

how does 3C malonyl CoA go to 16C

A

Fatty acid synthase enzyme adds two carbons to make palmitic acid

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59
Q

how does 16C palmitic acid go to 18C

A

Elongase enzyme adds two carbons to make stearic acid

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60
Q

how does 18C go to 18C with a double bond (monounsaturated)

A

Delta9-desaturase enzyme insert double bond to make oleic acid

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61
Q

when is ATP produced from acetyl CoA

A

Produce ATP when acetyl CoA broken into CO2 – need energy

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62
Q

how is acetyl CoA transported into the cytosol

A

Acetyl CoA itself wont cross mitochondrial membrane, have to temporarily make it into citrate molecule by combining it with oxaloacetate
Specific transporter lets citrate across membrane
When citrate on other side it is broken down again to get acetyl CoA
Oxaloacetate is broken back down into pyruvate which moves back into the mitochondria

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63
Q

where is acetyl CoA made

A

mitochondria

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64
Q

where are fatty acids synthesised

A

cytosol

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65
Q

what mechanism is used to transport acetyl CoA

A

So need to get it out the mitochondria by using a shuttle mechanism

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66
Q

in fatty acid synthesis what is the rate limiting enzyme

A

Acetyl CoA carboxylase, first step which regulates the rate at which fatty acids are made

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67
Q

what is the fatty acid synthesis of prokaryotes

A

synthesis occurs due to the action of a series of separate enzymes

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68
Q

what is the fatty acid synthesis of eukaryotes

A

synthesis occurs through the action of a multifunctional enzyme complex

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69
Q

what is linked to acyl carrier protein

A

Intermediates in fatty acid synthesis

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70
Q

what is ACP

A

acyl carrier protein

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71
Q

what is ACP in bacteria

A

77 amino acid protein joined to a phosphopantetheine (PP) group

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72
Q

what is ACP part of in animals

A

part of the fatty acid synthase complex

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73
Q

what is the acetyl transacylase reaction

A

Acetyl CoA joins with ACP temporarily form acetyl ACP+CoA

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74
Q

what is the malonyl transacylase reaction

A

Malonyl CoA joins with ACP temporarily form malonyl ACP+CoA

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75
Q

what does fatty acid synthase system do

A

synthesizes long chain saturated fatty acids

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76
Q

what does the fatty acid synthase system involve in prokaryotes

A

four separate enzymes

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77
Q

what are the substrates in fatty acid synthase

A

Acetyl-ACP
Malonyl-ACP
NADPH

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78
Q

what are the steps in the fatty acid synthase reaction

A

Start with acetyl ACP 2C fatty acid, reacts with malonyl ACP 3C, requires reducing power from 2 NADPH molecules
NADPH oxidized to make NADP+
One of the carbons from malonyl CoA lost as CO2
Lose some water
2 carbons from malonyl-ACP added to acetate to make butryl-ACP 4 C

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79
Q

what process occur in the fatty acid synthase reaction

A
  1. Condensation
  2. Reduction
  3. Dehydration
  4. Reduction
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80
Q

what happens in chain elongation

A

Every step added another two C

Lose a C as CO2

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81
Q

what is chain termination

A

uses a water from synthesis of palmitate

carbon chain tend to stop at C16, release palmitic acid

82
Q

what releases palmitic acid in chain termination

A

thioesterase enzyme

83
Q

where are shorter chains usually released (chain termination)

A

Some shorter chain fatty acids are also released, particularly in mammary gland

84
Q

what is the major product of fatty acid synthase reaction

A

palmitic acid

85
Q

how many carbon atoms are in 60% of fatty acids

A

60% of fatty acids in human adipose tissue have 18 Carbon atoms

86
Q

where are fatty acids from

A

Diet (plants and animals)
Further metabolism of palmitate - Can further elongate palmitate and add extra two carbons and make 18 carbon fatty acids

87
Q

where is palmitic acid made

A

cytoplasm

88
Q

where is stearic acid made

A

Some of the palmitic acid moves to the endoplasmic reticulum
Palmitic acid to stearic acid, adding two extra carbons using elongase occurs on endoplasmic reticulum

89
Q

where is oleic acid made

A

Also on endoplasmic reticulum stearic acid made into oleic acid, delta9–desaturase acts on the ninth carbon from carboxyl end and can insert double bond between ninth and tenth carbon probably

90
Q

what is the most abundant fatty acid in nature

A

Oleic acid

91
Q

name some important1-acyl glycerol phosphate 2-acyltransferase phospholipids

A

phosphatidylcholine
phosphatidylethanolamine
phosphatidylserine
phosphatidylinositol

92
Q

what are phospholipids important in

A

major components of biological membranes

role in cell signalling

93
Q

what is the difference in the first step of triacylglycerol and phospholipids synthesis

A

they’re the same
glycerol-3-phosphate converted to lysophosphatidate

a fatty acid, which is attached to Co factor Co enzyme A​
Release fatty acid from Co enzyme A and join it to the first carbon​
G-3-P produces lysophosphatidate (added a fatty acid on first carbon)​
Often is a saturated fatty acid added on first carbon​

94
Q

what are glycerol-phospholipids

A

all phospholipids with glycerol backbone

95
Q

what is phosphidate

A

Phosphatide is a glycerol with two fatty acids, one on first carbon, second on second carbon​

96
Q

what happens to lysophosphatidate in triacylglycerol and phospholipid synthesis

A

Fatty acid joined to Co enzyme A, released from enzyme and fatty acid joins to second carbon​

97
Q

what does triacylglycerol and phosphoplipid synthesis start with

A

Normally start with a glycerol that has phosphate on third carbon – glycerol-3-phosphate​

98
Q

what can happen to phosphatidate

A

can take 2 routes phosphatide can take​

Can remove phosphate group from third carbon using phosphatidate phosphohydrolase enzyme, so replaced with hydroxyl group – diacylglycerol ​

Take nucleotide CTP, and CDP molecule added to last carbon form CDP-diacylglycerol

99
Q

what causes the different routes for phosphatidate

A

Depending on the metabolic state of the cell, and requirements of cell which is made

100
Q

how can phosphatidate form triacylgylcerol

A

Form diacylglceryol by adding another fatty acid to last carbon to form triacylglycerol

101
Q

what does diacylgylcerol make

A

Phosphotidylcholin and Phosphotidylethanolamine phospholipids, these make Phosphotidylserine

102
Q

what does CDP-diacylgylcerol form

A

Phosphotidylinostitol

103
Q

what does phosphidate form

A

diacylglycerol

CDP-diacylglycerol

104
Q

what happens in lipid transport

A

eat them, digest and absorb them need to move fatty acids round body to different tissues often directly to adipose tissue​
Plasma of blood is water based media
Transport out of intestine​

105
Q

why is it important to be able to store

A

need to be able to mobilise that energy when fasting as a source of energy​

106
Q

where are lipids made

A

Store and make lipids in liver, then has to mobilise and transport them​

107
Q

where are lipids stored

A

adipose tissue

108
Q

where are lipids used

A

muscles​

109
Q

where are triacylglycerols stored

A

Adipose tissues

110
Q

what are NEFA

A

non-esterified fatty acids

111
Q

what happens with non-esterified fatty acids in lipid transport

A

NEFA can be released from adipose tissue and loosely stick to protein, albumin –major protein in blood produced by the liver, has hydrophobic regions on it which fatty acids seek out and temporarily attach to transported to muscle and released. Taken into muscle cells and used as energy source

112
Q

what happens with intestine and liver in lipid transport

A

Intestine and liver make complicated particles – lipoproteins. Is a sphere, ball shaped lipoprotein has a coating of phospholipids hydrophilic due to the polar heads being on the outside, so will physically dissolve in the plasma

113
Q

what is a lipoprotein like

A

Hydrophobic fatty acid tail on inside ​
molecules of cholesterol dotted in the outer coating ​
Lipids inside that don’t like water e.g. triacylglycerol extremely hydrophobic

114
Q

what is cholesterol ester like

A

very hydrophobic

115
Q

what are the components of lipoproteins

A

proteins - apolipoproteins
phospholipids - phosphatidylcholine most abundant
triacylglycerol
cholesterol and cholesterol ester

116
Q

where is cholesterol in lipoproteins

A

free cholesterol at surface

117
Q

where is cholesterol ester in lipoproteins

A

attached to fatty acid in core

118
Q

how do lipoprotein classes differ

A

protein/lipid ratio
phospholipid/cholesterol/cholesterol ester/ triacylglycerol ratio​
specific proteins present

119
Q

how do physical difference occur in lipoprotein

A

size​
Density (chylomicrons big but light as full of lipid)​
Charge (depends which proteins they have, can separate individual lipoproteins using gel electrophoreis)

120
Q

which lipoproteins are not named by classification

A

Lipoproteins produces by intestine not named by classification, these are the chylomicrons

121
Q

why do many chylomicrons float

A

are less than 1 density so float

water is 1

122
Q

what is VLDL

A

very low density liopoprotein

density lessthan 1.006

123
Q

what is IDL

A

intermediate density lipoprotein

124
Q

what is LDL

A

low dense lipoprotein

125
Q

what is HDL

A

high dense lipoprotein

126
Q

why must those who’s lipid profile is being measure told to not to eat

A

chylomicrons are hard to completely seperate from VLDL

127
Q

what are apolipoproteins

A

diverse group of proteins that associated with lipoproteins

128
Q

how come apolipoproteins can jump around different molecules

A

most proteins are only loosely associated with surface

129
Q

what are the apolipoproteins functions

A

structural
enzyme activators or inhibitors
receptor recognition

130
Q

what are the apolipoproteins structural function

A

Hold particle together​

e.g. ApoB48 & ApoB100

131
Q

what are the apolipoproteins enzyme activators or inhibitors function

A

e.g. Apo CII – activates lipoprotein lipase/ ApoCIII - inhibits lipoprotein lipase

132
Q

what are the apolipoprotein receptor recognition functions

A

Recognised by receptors on the surface of cells​

e.g. ApoB100 recognised by LDL receptor​

133
Q

what does e.g. B48 in a apolipoprotein mean

A

B48 is 48% of the size of B100

134
Q

which lipoprotein is the most simple

A

LDL as only has B100

135
Q

what are the lipoprotein synthesis and secretion paths

A

exogenous path
endogenous path
reverse cholesterol transport path

136
Q

what happens in the exogenous path of lipoprotein metabolism

A

Dietary fats mainly fatty acids leave intestine in a chylomicron​ released into lymphatic system, enter blood stream, catches chylomicron, anchored to it
enzyme breaks triacylglycerol inside and release fatty acids
Chylomicron delivers a lot of its fat to adipose tissue, producing chylomicron remnants ​
Chylomicron remnant is delivered to the liver

137
Q

what happens in the endogenous path of lipid metabolism

A

VLDL released from liver into circulation, pass into capillaries of tissues, interacts with lipoprotein lipase, either in muscle or adipose tissue
VLDL acted on lipoprotein lipase, breaks down triacylglycerol inside it, releases fatty acids and migrate to tissues
Remnant particle of VLDL is IDL, half of the IDL directly removed

138
Q

how can heart disease be caused

A

Some LDL can be deposited in arteries = bad, causes heart disease

139
Q

what happens in the reverse cholesterol transport path

A

Nascent HDL grows round the body and picks up cholesterol and delivers it to liver​
Liver takes large amounts of cholesterol​
Tissues cant break cholesterol

140
Q

where is VLDL made

A

liver

141
Q

where does most VLDL get directed

A

most VLDL will be directed to muscle rather than adipose tissue

142
Q

how is the remnant IDL removed in lipoprotein metabolism - endogenous

A

circulates through the liver (50% removed from liver by interacting with receptors) and other 50% is acted on by another enzyme hepatic lipase, which is in the liver further breaks it to LDL​

Of the LDL 80% circulates back to the liver and is removed and the other 20% taken up by peripheral tissues ​

143
Q

what is crucial in regulating LDL

A

Liver is crucial in regulating how much LDL is in the blood

144
Q

why is there competition in lipoprotein metabolism

A

Competition for LDL between these two paths ​

Both occur simultaneously

145
Q

what is the tissue of origin for exogenous

A

intestine

146
Q

what is the tissue of origin for endogenous

A

liver

147
Q

what is the exogenous particle

A

chylomicron

148
Q

what is the endogenous particle

A

VLDL

149
Q

what is the site os secretion for exogenous

A

lymph/blood

150
Q

what is the site of secretion for endogenous

A

blood

151
Q

what is the exogenous ApoB form

A

apoB48

152
Q

what is the endogenous ApoB form

A

apoB100

153
Q

what is the exogenous remnant

A

chylo remnant

154
Q

what is the endogenous remnant

A

IDL/LDL

155
Q

what is the site is uptake for exogenous

A

liver

156
Q

what is the endogenous site of uptake

A

liver/peripheral

157
Q

what is the exogenous receptor

A

LRP/LDL

158
Q

what is the endogenous receptor

A

LDL

159
Q

what is the exogenous ligand

A

apoE

160
Q

what is the endogenous ligand

A

apoE/apoB100

161
Q

what is LCAT

A

lecithin:cholesterol-acyl transferase

162
Q

what shape is newly formed HDL

A

disc-shaped

163
Q

what happens when cholesterol and phospholipid combine

A

use LCAT enzyme
form
- cholesterol ester
- lysophospholipid

164
Q

how is HDL converted to spherical HDL

A

Cholestrol ester moves to center of the partical (as hates water)​
and becomes a spherical lipoprotein

165
Q

when does HDL3 become HDL2

A

HDL3 continues to accumulate cholesterol ester and makes HDL2
HDL moves round body getting more cholesterol
HDL2 goes to liver when cant physically collect more, then liver can make them into e.g. bile acids, then excreted in faeces, major way to remove cholesterol

166
Q

how is cholesterol removed from HDL2

A

HDL2 will associate to the liver and pump the cholesterol ester into the liver, shrinks to become HDL3 and then goes to collect more cholesterol ester

167
Q

what happens to fatty acids when they get into cells

A

adipose tissue
liver
muscle

168
Q

what happens to fatty acids in adipose tissues

A

stored as triacylglycerol (energy source)

169
Q

what happens to fatty acids in liver

A

form either

  • triacylglycerol phospholipid
  • acetyl CoA which forms CO2 and ketone bodies
170
Q

what happens to fatty acids in muscle

A

acetyl CoA forms CO2

In the fast state/starved can used acetyl CoA, feed into TCA cycle to make energy it needs

171
Q

what energy is used in fed state

A

will mainly use glucose

172
Q

when is ketone bodies made

A

if starving the acetyl CoA may be used to make ketone bodies as an alternative fuel for body​
In starvation fatty acids can be used for ketogenesis to make ketone bodies​

173
Q

what is adipocyte

A

adipose tissue

174
Q

what is the structure of fatty acid in adipose tissue

A

Big droplet of lipid in centre of cell cytoplasm tends to be pushed towards the outside, nucleus often pushed against plasma membrane

175
Q

what causes liver disease

A

when obese resistant to insulin, so cant break down the lipid droplets – main cause of liver disease

176
Q

what happens to fatty acids in fasted state

A

most FA will go muscle​

177
Q

where does and what is glycogenesis

A

Liver capable of taking glucose and fructose made into sugar glycogenesis​

178
Q

how can the liver use fatty acids in liver to get energy

A

Liver can use some for beta oxidation to get some energy​

Fatty acids fed into beta-oxidation, breaking down fatty acid to acetyl CoA then used in TCA cycle to get ATP

179
Q

what is the alternative energy source for muscles

A

muscle use fatty acids

if low glucose

180
Q

in fed state what is the fatty acid metabolism in muscle

A

in fed state can be from chylomicrons​

In both the fed and fat state can be from VLDL, fatty acids released by lipoprotein lipase​

181
Q

in the starved state what is the fatty acid metabolism in muscle

A

can be from non-esterified fatty acid released through adipose tissue​

182
Q

what are the three sources of fatty acids for energy

A

Released by LPL from chylomicrons​
Released by LPL from VLDL​
Released as NEFA from adipose tissue

183
Q

what is the overall energy yield from palmitic acid

A

106 ATP

184
Q

what is the site in the cell of fatty acid synthesis

A

cytosol

185
Q

what is the carrier molecule of fatty acid synthesis

A

ACP

186
Q

what is the site in the cell of fatty acid oxidation

A

mitochonria

187
Q

what is the carrier molecule of fatty acid oxidation

A

CoEnzyme A

188
Q

what is the enzymes fatty acid synthesis

A

multifunctional enzyme

189
Q

what is the enzymes fatty acid oxidation

A

separate enzymes

190
Q

what is the carbon units fatty acid synthesis

A

2C added from (3C) malonyl-CoA

191
Q

what is the carbon units fatty acid oxidation

A

yields (2C) acetyl-CoA

192
Q

what is the CoFactor of fatty acid synthesis

A

uses NADPH

193
Q

what is the CoFactor of fatty acid oxidation

A

yields NADPH, can feed into electron transport chain

194
Q

what is the fatty acid metabolism in the liver

A

Liver can receive FA from chylomicron remnants ​
newly synthesized fatty acids through lipogenesis​
Can take fatty acids and re-esterify them and package them into VLDL and secrete them, if this system becomes overloaded then can store fat as little droplets in its own cells, fine as a temporary measure, will mobilise the fat again when don’t need it​

195
Q

what happens in fatty acid oxidation

A

linked to CoA before degradation​
Need to link fatty acids back to Co enzyme A using acyl CoA synthase using up a molecule of ATP, to generate a lot more ​

196
Q

how is acyl-CoA formed

A

fatty acids enter cytosol of cell, move into mitochondria
temporary shuttle, using molecule carnitine ​
catalyzed by CPT​
Acyl CoA temporarily breaks down, fatty acid group is attached to a carnitine, transports it across mitochondrial membrane​
Another Co enzyme A reattaches it to fatty acid, releasing carnitine, which can go back into cytoplasm and reused​
Once in mitochondira beta-oxidation can start

197
Q

what is the first stage in fatty acid oxidation

A

two CH2 molecules
oxidation, removal of hydrogen
generates FADH2 from FAD (energy can be fed into electron transport chain)​

198
Q

what is the second stage of fatty acid oxidation

A

add water – hydration, break double bond and add hydroxyl group to first carbon in double bond and hydrogens on second​

199
Q

what is the third stage of fatty acid oxidation

A

another oxidation
NADH2 forms from NAD (more energy that can feed into electron transport)​
Broken down hydroxyl group and replaced with double bond, leading to an oxygen​
Ready to release some carbons in the form of acetyl CoA

200
Q

what happens in the last stage of fatty acid oxidation

A

release second carbon in and original carboxyl group​
C=O becomes new carboxyl group and Co enzyme A comes in and joins it ​
produce FA that’s got two less carbons, continue till broken down whole of fatty acid, all carbons released as acetyl CoA

Biochemistry (13 decks)

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