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Principles > Biochemistry > Flashcards

Biochemistry Flashcards

1
Q

What are examples of lipids?

A

Triglycerides, phospholipids, steroids

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2
Q

What is an example of a monosaccharide?

A

Glucose

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3
Q

Which carbons react with each other in monosaccharides and what do they form?

A

Carbon 1 and carbon 5 to form a cyclic compound

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4
Q

What type of reaction is combining carbons of the same monosaccharide to form a cyclic compound?

A

Intermolecular reaction to change the structure of a molecule

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5
Q

What type of bonds can disaccharides be held together with?

A

Alpha or beta linkages

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6
Q

What is the importance of different types of bonds in disaccharides?

A

Important in our ability to break bonds apart during metabolism

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7
Q

In disaccharides, which carbons are the alpha or beta linkages between?

A

1 and 4

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8
Q

What two things do reactions involve a change in?

A

Entropy and enthalpy

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9
Q

What is the equation for a free energy change in a reaction?

A

delta G= delta H - T(deltaS)

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10
Q

What are exergonic reactions?

A

Total free energy of products is less than reactants- delta G is negative and these can occur spontaneously

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11
Q

What are endergonic reactions?

A

Total free energy of products is more than reactants- delta G is positive and these need energy to occur

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12
Q

What are delta G values of near 0 characteristic of?

A

Readily reversible reactions

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13
Q

What are examples of unfavourable cellular processes (+ delta G)?

A

Transport against a gradient or synthesis of large molecules

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14
Q

What are unfavourable cellular processes driven by?

A

Coupling

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15
Q

What reaction is very favourable and is often coupled?

A

Formation of ADP + Pi

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16
Q

What causes ATP to be less stable than ADP?

A

negative charges are very close together

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17
Q

How is the strain on ATP reduced partially?

A

Removal of a phosphate group

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18
Q

What are anhydride bonds?

A

High energy bonds

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19
Q

What are reactions with large negative delta G values used for in metabolic reactions?

A

Control points

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20
Q

What is metabolism?

A

All reactions taking place in the body

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21
Q

What is catabolism?

A

Breaking down smaller molecules into complex ones to release energy (favourable)

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22
Q

What is anabolism?

A

Synthesising complex molecules out of small ones in energy consuming unfavourable reactions

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23
Q

What is an example of a catabolic reaction?

A

Glycolysis (breakdown of glucose to generate ATP)

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24
Q

What is the net gain of glycolysis?

A

2 ATP

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25
Q

What is an example of anabolism?

A

Gluconeogenesis- making new glucose from non-carbohydrate precursors

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26
Q

What is the polarity of water?

A

Polar

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27
Q

What is the shape of water?

A

Bent

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28
Q

Water is hydrophilic. What dissolves in it?

A

Ionic and polar substances

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29
Q

What substances are insoluble in water?

A

Non-polar substances

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30
Q

How strong are hydrogen bonds compared to covalent ones?

A

Weaker individually but may be stronger collectively

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31
Q

What are amphipathic molecules?

A

Both hydrophobic and hydrophilic

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32
Q

What do amphipathic molecules form in water?

A

Micelles

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33
Q

What does the chiral carbon of an amino acid bind to?

A

An amino group, carboxyl group, hydrogen and side chain

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34
Q

What are the D and L forms of amino acids?

A

Stereoisomers

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35
Q

What bonds form between amino acids?

A

Peptide

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36
Q

What describes an acid?

A

Donates protons

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37
Q

What describes a base?

A

Accepts protons

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38
Q

What is the strength of an acid based on?

A

How readily it dissociates

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39
Q

What is the equation for the dissociation constant of an acid?

A

Ka= [H+] [A-] / [HA]

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40
Q

What is pH a measure of?

A

Concentration of protons in a solution

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41
Q

What does the Henderson-Hasselbach equation do?

A

Connects the Ka of a weak acid with the pH of the solution containing it

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42
Q

What is the Henderson-Hasselbalch equation?

A

pH= pKa + log ([A-] / [HA])

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43
Q

What is the isoelectric point?

A

pH at which a molecule has no net charge

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44
Q

How many pKa values do amino acids have?

A

2

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45
Q

What is primary protein structure?

A

The amino acid sequence

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46
Q

What is secondary protein structure?

A

Localised conformation of polypeptide backbone

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47
Q

What is the 3D structure of a polypeptide, including side chains?

A

Tertiary structure

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48
Q

What is the arrangement of polypeptide chains in a protein with multiple subunits?

A

Quaternary structure

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49
Q

What type of bonds are involved in secondary structure?

A

Hydrogen bonds

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50
Q

Secondary structure is localised. What does this mean?

A

Similar features are kept together

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51
Q

What are types of secondary structure?

A

Alpha helices, beta sheets, triple helices

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52
Q

What forms hydrogen bonds in secondary structure?

A

CO group of one amino acid and the NH group of another- 4 amino acids away

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53
Q

What residues break alpha helices?

A

Proline

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54
Q

How many polypeptide chains are involved in alpha helices?

A

1

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55
Q

How many polypeptide chains are involved in beta sheets?

A

Can be more than 1

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56
Q

What two types of bets-sheets are there?

A

Parallel or anti-parallel

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57
Q

Can different elements of secondary structure occur between the same protein?

A

Yes

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58
Q

What forms a triple helix?

A

Collagen

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59
Q

Where is collagen found in the body?

A

Bone and connective tissue

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60
Q

What is a repeating sequence of an amino acid?

A

Triple helix

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61
Q

What type of inter-chain bonds are present in triple helices?

A

Hydrogen

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62
Q

Apart from hydrogen, what other type of bonds are present in triple helices?

A

Covalent bonds

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63
Q

What are globular proteins?

A

Proteins folded into a spherical shape

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64
Q

What is an example of a globular protein?

A

Haemoglobin

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65
Q

What is the solubility of globular proteins like?

A

Soluble in water and salt solutions

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66
Q

What are fibrous proteins?

A

Contain polypeptide chains organised approximately parallel along a single axis

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67
Q

What are examples of fibrous proteins?

A

Keratin, collagen

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68
Q

What is the solubility of fibrous proteins?

A

Not soluble in water and salt

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69
Q

What are stronger, fibrous or globular proteins?

A

Fibrous

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70
Q

What are some different bonds involved in tertiary structure?

A

Hydrogen bonds, hydrophobic interactions, salt bridges, disulfide bridges

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71
Q

What are disulphide bridges?

A

Covalent bonds between cysteine amino acids

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72
Q

What are proteins which aid the folding process known as?

A

Chaperones

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73
Q

What conditions can cause denaturation of proteins?

A

pH, heat, detergents, urea, thiol or reducing agents

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74
Q

What are prosthetic groups?

A

A type of tertiary structure- proteins which contain another non-protein structure

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75
Q

What is an example of a prosthetic group?

A

Haem

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76
Q

What is quaternary structure involved in?

A

Proteins involving more than one polypeptide chain

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77
Q

What happens when one subunit of a protein binds to oxygen and what is this process known as?

A

Increases the other subunits affinity for oxygen- allosteric regulation

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78
Q

What is the genome?

A

The total DNA in each cell

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79
Q

What are the sugars in RNA and DNA?

A

Ribose and deoxyribose

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80
Q

What is a nucleoside?

A

Base and sugar

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81
Q

What is a nucleotide?

A

Nucleoside and phosphate group

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82
Q

What bonds are involved in nucleotides?

A

Phosphodiesterase

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83
Q

What are phosphodiesterase bonds formed between in nucleotide binding?

A

Free 3’ OH group and 5’ triphosphate

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84
Q

How many high energy bonds does the phosphodiesterase bonding of nucleotides take up?

A

2

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85
Q

Where are new nucleotides added?

A

To the free 3’ end only

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86
Q

How many nucleotide strands does DNA contain?

A

2

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87
Q

What is on the outside of the DNA strand?

A

Sugar phosphate backbones

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88
Q

What is on the inside of the DNA strand?

A

Bases

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89
Q

How are base pairs bonded?

A

Hydrogen bonds

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90
Q

What are the differences in bonds between AT and CG pairs?

A

AT- double bond

CG- triple bond

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91
Q

What must happen to DNA before cell division?

A

Replication

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92
Q

DNA replication is semi-conservative and catalysed by what?

A

RNA polymerase

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93
Q

What is needed to start DNA replication?

A

RNA primer

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94
Q

Where can DNA be added?

A

Only to existing nucleotides

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95
Q

Where does DNA replication start?

A

Simultaneously at multiple points in the genome

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96
Q

How is the lagging strand replicated?

A

In small short segments known as Okazaki fragments

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97
Q

What does helicase do?

A

Unwinds the DNA helix and stops it rewinding

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98
Q

What does 3’-5’ exonuclease do?

A

Removes incorrect nucleotides to improve error rate

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99
Q

What is rRNA?

A

Combines with proteins to form ribosomes where protein synthesis takes place

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100
Q

What is tRNA?

A

Carries amino acids to be incorporated into the protein

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101
Q

What is mRNA?

A

Carries genetic information for protein synthesis

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102
Q

Where does the specific amino acid attach to tRNA?

A

3’ end

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103
Q

What happens at the RNA polymerase binding stage of transcription?

A

Detection of initiation sites on DNA, requires transcription factors

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104
Q

What is the 2nd stage of transcription?

A

DNA chain separation

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105
Q

What is the 3rd stage of transcription?

A

Transcription initiation

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106
Q

What are the 4th and 5th stages of transcription?

A

Elongation and termination

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107
Q

Where does transcription start?

A

Nucleotide +1

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108
Q

What is a TATA box?

A

A nucleotide sequence which specifies to other molecules where transcription begins

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109
Q

Where is the TATA box found?

A

About 25 nucleotides infront of the transcriptional start

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110
Q

What does the TATA box binding protein do?

A

Recognises TATA and introduces a kink into DNA which determines the transcriptional start and direction

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111
Q

What direction is the RNA chain synthesised in?

A

5’-3’

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112
Q

What is new RNA identical and complementary to?

A

Identical to coding strand

Complementary to template strand

113
Q

What does regulation of transcription require?

A

DNA binding proteins

114
Q

What are the functional domains of DNA binding proteins?

A

DNA binding domain and transcription activation domain

115
Q

What are non-coding sequences that eukaryotic genes have?

A

Introns

116
Q

Introns have to be removed before translation- how?

A

Splicing

117
Q

Why does one end of mRNA receive a GTP cap?

A

To prevent degradation

118
Q

Why does one end of mRNA receive a polyA tail?

A

To make it ready to be recognised for translation

119
Q

What do anticodons of tRNA molecules form base pairs with?

A

Codons on mRNA

120
Q

What does degenerate genetic code mean?

A

Amino acids have more than 1 codon

121
Q

What does unambiguous genetic code mean?

A

Each codon codes for only 1 amino acid or a stop

122
Q

How many different frames can an RNA molecule be translated in?

A

3

123
Q

What do aminoacyl-tRNA synthetases do?

A

Bind amino acids to their tRNA molecule

124
Q

How many rRNA molecules and protein compounds do ribosomes contain?

A

4

125
Q

How many tRNA binding sites do ribosomes have?

A

3

126
Q

What happens to GTP in the initiation phase of translation?

A

Hydrolysed

127
Q

Where do ribosomal subunits bind in initiation of translation?

A

5’ end of mRNA

128
Q

What is the start codon?

A

AUG

129
Q

At the end of initiation, where is the initiator tRNA located?

A

P site

130
Q

In elongation of translation, where does elongation factor bring the next tRNA to?

A

A site

131
Q

What do peptidyl transferases do?

A

Catalyse peptide bond formation between amino acids

132
Q

During translocation, where does tRNA with the growing peptide move?

A

P site

133
Q

When does termination of translation take place?

A

When the A site of the ribosome encounters a stop codon

134
Q

What is a point mutation?

A

Change in a single base of DNA

135
Q

What is a missense mutation?

A

Change of amino acid sequence

136
Q

What is a nonsense mutation?

A

Creates a new termination codon and leads to premature stop

137
Q

What is a silent mutation?

A

No change in amino acid sequence

138
Q

What is a frameshift mutation?

A

Addition/deletion of 1 or 2 bases

139
Q

What kind of mutations affect a larger portion of the genome?

A

Chromosomal

140
Q

What are different types of chromosomal mutation?

A

Deletion, duplication, translocation, inversion

141
Q

What is targeting after translation?

A

Moving a protein to its final location

142
Q

What is modification after translation?

A

Addition of further functional chemical groups to a protein

143
Q

What is degradation after translation?

A

Removal of unwanted/damaged proteins

144
Q

What do free ribosomes in the cytoplasm make proteins for?

A

Cytoplasm, nucleus, mitochondria

145
Q

What do bound ribosomes in the RER make proteins for?

A

Plasma membrane, ER, golgi

146
Q

What do enzymes do?

A

Speed up the rate at which a reaction reaches equilibrium

147
Q

What do enzymes not do?

A

Affect the equilibrium position of a reaction

148
Q

What is the transition state?

A

Reaction intermediate species which has the greatest free energy

149
Q

Where do enzymes specifically bind and stabilise?

A

Transition state

150
Q

What do enzymes provide alternative reaction pathways to do?

A

Reduce the activation energy

151
Q

What is glycogen storage disease?

A

An enzyme deficiency which results in the failure of glycogen to enter a phosphorylated state

152
Q

What are some symptoms of glycogen storage disease?

A

Hypoglycaemia, hepatomegaly, skin and mouth ulcers, bacterial and fungal infections, bowel inflammation and irritability

153
Q

What does the catalytic activity of many enzymes depend on?

A

Small molecules- cofactors and coenzymes

154
Q

What are co-factors?

A

Inorganic metalions

155
Q

What are coenzymes?

A

Organic molecules

156
Q

Which out of coenzymes and cofactors are permanently associated with the enzyme?

A

Cofactors

157
Q

What happens to coenzymes during a reaction?

A

They change charge and structure but are regenerated in the end

158
Q

What are tightly bound co-enzymes known as?

A

Prosthetic groups

159
Q

What does: the active site of unbound enzymes is complementary to the shape of the substrate describe?

A

Lock and key model of substrate binding

160
Q

What does: the binding of the substrate induces a conformational change in the enzyme which results in a complementary fit describe?

A

Induced fit model of substrate binding

161
Q

What are isoforms of enzymes known as?

A

Izozymes

162
Q

What do isozymes do?

A

Catalyse the same reaction but have different properties and substrates

163
Q

What is creatinine kinase?

A

A protein which binds to muscle sarcomere

164
Q

Where is the M form of creatinine kinase produced?

A

Skeletal muscle

165
Q

Where is the B form of creatinine kinase produced?

A

Brain

166
Q

What type of creatinine kinase does the heart produce?

A

Both B and M type heterodimer

167
Q

What does B type creatinine kinase in the blood suggest?

A

Stroke/tumour

168
Q

What does the heart heterodimer of creatinine kinase in the blood suggest?

A

Heart attack

169
Q

What does kinase do?

A

Phosphorylates other proteins

170
Q

What does phosphatase do?

A

Dephosphorylates other proteins

171
Q

What are zymogens?

A

Inactive precursors of enzymes

172
Q

How are zymogens transferred into active enzymes?

A

Cleavage of a covalent bond

173
Q

Where do zymogen reactions commonly occur?

A

Small intestine with digestive enzymes

174
Q

In enzyme kinetics, what is Vmax?

A

Maximum speed of catalysis

175
Q

In enzyme kinetics, what is Km?

A

The concentration of substrate which gives half Vmax

176
Q

In enzyme kinetics, what does k1 describe?

A

Forward rate constant for enzyme association with the substrate

177
Q

In enzyme kinetics, what does k2 describe?

A

Forward rate constant of enzyme conversion of substrate to product

178
Q

In enzyme kinetics, what does k-1 describe?

A

Backwards rate constant for enzyme dissociation with the substrate

179
Q

If given the graph of V and S moles in log form, which way is increasing substrate concentration?

A

Right to left

180
Q

If given the graph of V and S moles in log form, which way is velocity increasing?

A

Towards the x-axis

181
Q

If given the graph of V and S moles in log form, where is Vmax?

A

Y- intercept

182
Q

If given the graph of V and S moles in log form, where is Km?

A

Where the slope intersects with the x-axis

183
Q

Does Vmax change in competitive inhibition?

A

No

184
Q

Does Vmax change in non-competitive inhibition?

A

Yes, the competitors will have different Vmax values

185
Q

What type of curve to allosteric enzymes result in?

A

Sigmoidal

186
Q

What do allosteric enzymes show?

A

Co-operative behaviour

187
Q

What do allosteric factors modulate?

A

Enzyme kinetics behaviour

188
Q

What physiological term is associated with moving the oxygen haemoglobin curve left?

A

Haldane effect- increased saturation of haemoglobin with oxygen but less oxygen delivery to tissues

189
Q

What physiological term is associated with moving the oxygen haemoglobin curve right?

A

Bohr effect- decreased saturation of haemoglobin with oxygen but more oxygen delivery to the tissues

190
Q

What way will foetal haemoglobin, methaemoglobin and carboxyhaemoglobin move the oxygen haemoglobin curve?

A

Left

191
Q

What else moves the oxygen haemoglobin curve left?

A

Low [H+] (alkali), low pCO2, low 2,3-DPG, low temp

192
Q

What moves the oxygen haemoglobin curve right?

A

High [H+] (acid), high pCO2, high 2,3-DPG, high temp

193
Q

What type of reaction is the anabolism of glucose?

A

Endergonic and reductive (requires energy)

194
Q

What type of reaction is the catabolism of glucose?

A

Exergonic and oxidative (yields energy)

195
Q

What does ATP do during redox reactions?

A

Energy carrier

196
Q

What does NADPH + H+ and NADP + H+ do during redox reactions?

A

Electron carrier

197
Q

What does oxygen do in redox reactions?

A

Combines with leftover hydrogen to form water

198
Q

How can glucose be stored?

A

Glycogen, starch, sucrose, converted to lipids

199
Q

What is glucose oxidised to form?

A

CO2 and O2

200
Q

What does oxidisation of glucose through the pentose phosphate pathway form?

A

Ribose-5-phosphate

201
Q

What does ribose-5-phosphate do?

A

Precursor for nucleotide synthesis and DNA repair- essential for growth

202
Q

What is produced when glucose is fermented by anaerobic glycolysis?

A

Lactate

203
Q

What does lactate cause?

A

Rapid, inefficient ATP production

204
Q

What is formed when glucose is oxidised through aerobic glycolysis?

A

Pyruvate

205
Q

What does pyruvate produce?

A

ATP efficiently

206
Q

How can glucose be transported?

A

Via Na+/glucose symporters or passive facilitated diffusion glucose transporters

207
Q

Which glucose transporters are found in the brain and have low Km?

A

GLUT 1 and 3

208
Q

What glucose transporter is found in liver/beta cells, has a high Km and is insulin dependent?

A

GLUT2

209
Q

Where is GLUT4 found?

A

In muscle and adipose tissue- insulin dependent

210
Q

What does GLUT5 do?

A

Transports fructose in the gut

211
Q

What is glycolysis?

A

Conversion of glucose to pyruvate

212
Q

What is formed in glycolysis?

A

2 pyruvate, 4ATP, 2H2O, 2NADH, 2H+

213
Q

What is the end point of pyruvate?

A

3 carbon chain with no phosphate

214
Q

How often does the 2nd part of glycolysis occur?

A

Twice for every mole of glucose

215
Q

What is the net gain of glycolysis?

A

2ATP

216
Q

What does hexokinase control?

A

Rate of substrate entry

217
Q

What does phosphofructokinase control?

A

Rate of flow

218
Q

What does pyruvate kinase control?

A

Product exit

219
Q

What is the ATP/AMP ratio known as?

A

Energy charge

220
Q

If adenyl nucleotides are in the shape of ATP what is the ATP/AMP ratio?

A

Charged

221
Q

What makes the ATP/AMP ratio discharged?

A

Cell only contains AMP and Pi

222
Q

What happens if the mitochondrial metabolism is inhibited by lack of oxygen?

A

NADH is used to ferment pyruvate to lactic acid

223
Q

When is NADH regenerated after anaerobic respiration?

A

Stage 3

224
Q

What is the Warburg effect?

A

Cancer cells produce energy by a high rate of glucose metabolism to lactate. They have a low Km.

225
Q

What are advantages of the Warburg effect?

A

Rapid energy production and rapid cell growth

226
Q

What are disadvantages of the Warburg effect?

A

Uses lots of glucose and causes weight loss

227
Q

What happens to NAD+ after glycolysis?

A

It turns to NADH + H+

228
Q

What must happen to NADH + H+ for glycolysis to continue?

A

Must be re-oxidised

229
Q

How is NAD+ regenerated?

A

Oxidative metabolism of pyruvate

230
Q

Before being re-oxidised, what does NADH do?

A

Delivers electrons to the respiratory chain (cytochrome system)

231
Q

Where does the TCA cycle occur?

A

Mitochondrial matrix

232
Q

How does pyruvate enter the mitochondrial matrix?

A

H+ gradient from the cytosol allows transport which occurs through facilitated diffusion

233
Q

What does pyruvate dehydrogenase complex do?

A

Catalyses the pyruvate to acetyl CoA reaction

234
Q

What does pyruvate dehydrogenase complex consist of and how is it regulated?

A

Consists of 3 enzymes which are allosterically regulated by phosphorylation

235
Q

Is the reaction of pyruvate to acetyl CoA reversible?

A

No

236
Q

Apart from pyruvate, what else can acetyl CoA be generated from?

A

Lipids or amino acids

237
Q

How many reactions are there in the TCA cycle?

A

8

238
Q

What does the 2C unit (acetyl CoA) combine with in the TCA cycle?

A

4C unit

239
Q

In the TCA cycle, the 6C unit is decarboxylated twice- what does this yield?

A

CO2

240
Q

What else do oxidation reactions in the TCA cycle form?

A

NADH + H+ and FADH2

241
Q

What energy is formed in the TCA cycle?

A

1 GTP

242
Q

What happens to the 4C unit at the end of the TCA cycle?

A

It is regenerated

243
Q

Where are all TCA enzymes found apart from one?

A

Mitochondrial matrix

244
Q

Where is the succinate dehydrogenase enzyme found?

A

Inner mitochondrial membrane

245
Q

What is high ATP, NADH and acetyl CoA suggestive of?

A

Plenty of energy

246
Q

What is high ADP and NAD+ suggestive of?

A

Lack of energy

247
Q

In the TCA cycle, what is generated per molecule of glucose?

A

4ATP, 10 NADH, 10 H+, 2 FADH2 and 6CO2

248
Q

What is pyruvate dehydrogenase complex deficiency?

A

X linked disease

249
Q

What will XX and XY forms of pyruvate dehydrogenase complex deficiency show?

A

XX- symptoms will show in adolescence

XY- stillborn

250
Q

What are some symptoms of pyruvate dehydrogenase complex deficiency?

A

Poor muscle tone, lack of coordination, retardation and seizures, persistent lactic acidosis and respiratory problems

251
Q

What does fumarate hydratase deficiency show?

A

Multiple systemic benign and malignant tumours- particularly tumours

252
Q

From both previous cycles, what does NADH + H+ and FADH2 carry at the start of oxidative phosphorylation?

A

Each molecule carries 2 high energy electrons

253
Q

What are the high energy electrons carried by NADH + H+ and FADH2 used for in oxidative phosphorylation?

A

To reduce O2 to H2O

254
Q

In oxidative phosphorylation, protons flow from the matrix to the inner membrane and back again following their concentration gradient. What does this do?

A

Provides energy to allow ADP to be phosphorylated to ATP

255
Q

What is used to overcome the fact that NADH cannot cross the inner mitochondrial membrane?

A

Glycerol 3 phosphate and aspartate shuttles

256
Q

What is the standard electron transfer of a reduced substance a measure of?

A

How readily substance X will donate an electron (compared to H2)

257
Q

What does a negative electron transfer value mean?

A

Reduced forms of substance X have a lower affinity for electrons than H2

258
Q

What does a positive electron transfer value mean?

A

Reduced forms of substance X will have a higher affinity for electrons than H2

259
Q

What is the standard free energy change proportional to?

A

Change in standard redox potential and the number of electrons transferred

260
Q

What is the driving force of oxidative phosphorylation?

A

Redox of O2 by NADH

261
Q

How many multisubunit respiratory complexes are involved in the electron transfer stage of oxidative phosphorylation?

A

4

262
Q

What do the multisubunit respiratory complexes are involved in the electron transfer stage of oxidative phosphorylation do?

A

Take energy from NADH and transfer it to oxygen to form water

263
Q

What are cytochromes?

A

Proteins which contain a haem group as a co-factor

264
Q

What does the Fe (II) in haem do?

A

Take up and release electrons

265
Q

What is transport of electrons through the respiratory chain coupled to?

A

Transport of H+ from the matrix to membrane

266
Q

How do protons travel back to the mitochondrial matrix from the inner membrane?

A

Through ATP synthase in 2 proton pumps

267
Q

What does the F1 subunit of ATP synthase do?

A

Protrudes into the mitochondrial matrix

268
Q

What does the F0 subunit of ATP synthase do?

A

Hydrophobic complex in the inner membrane

269
Q

What does the flow of proteins through ATP synthase do?

A

Causes ATP synthesis

270
Q

What are examples of competitive inhibitors of the electron transport chain?

A

Cyanide, azide and CO

271
Q

What provides a route for protons to be returned to the matrix?

A

Uncoupling proteins

272
Q

How many ATP molecules does 1 glucose make?

A

30-32

273
Q

What is lipolysis?

A

The breakdown of lipids

274
Q

What does lipase do?

A

Releases free fatty acids and glycerol when energy is needed

275
Q

Where are ketone bodies found?

A

They are formed in liver mitochondria and diffuse into the bloodstream

276
Q

What are important molecules of energy metabolism which are strongly acidic?

A

Ketone bodies

277
Q

What does cholesterol do?

A

Maintains structure and fluidity of cell membranes, involved in cell signalling and act as precursors for bile/bile acids

278
Q

What do triglycerides require for transport?

A

Lipoproteins

Principles (11 decks)

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