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Flashcards in T4 Metabolism Deck (105)
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1
Q

What is a plasma glucose level of 2.5 mM?

A

Life threatening low

2
Q

What do odd chain fatty acids require for oxidation?

A

Vitamin B12

3
Q

Name the enzymes of the irreversible reactions of the TCA cycle.

A

Citrate synthase, isocitrate dehydrogenase, keto-glutarate dehydrogenase

4
Q

Describe stearic acid.

A

Unsaturated fatty acid with 18 carbons

5
Q

What % of 16-24 yo drink at least once a week?

A

50%

6
Q

When is glycerol converted to glucose and how?

A

In starvation by gluconegenesis

7
Q

Which hormone inhibits glycolysis and when?

A

Insulin in fed state, or during exercise

8
Q

How have alcohol related admissions changed from 2000-2010?

A

Doubled

9
Q

How soon after lung cancer diagnosis does death occur in half of diagnoses?

A

6 months

10
Q

How many UK adults have alcohol dependance?

A

1.5 million

11
Q

How what will be produced from complete oxidation of a fatty acid of length 16C?

A

8 acetyl CoA, 7NADH, 7FAD

12
Q

What is formed from metabolism of ketogenic amino acids?

A

Acetyl CoA —-> Fat or CO2 and H2O

13
Q

How much glucose in there in the blood usually?

A

10g

14
Q

When is galactose isomerised to glucose?

A

When attached to UDP

15
Q

What is the fate of pyruvate in aerobic conditions?

A

Decarboxylation and entry into TCA cycle

16
Q

What does ATP in reactions?

A

Alters position of equilibrium

17
Q

How much glucose is stored in the body in the fed state, how much of this is in the liver?

A

400g, 100g in the liver

18
Q

What % of premature deaths are due to low fitness?

A

16%

19
Q

How are odd-chain fatty acids broken down?

A

Using acetyl CoA and propionyl CoA

20
Q

What is produced in the link reaction?

A

CO2

21
Q

What is long term quit rate?

A

25%

22
Q

What are coenzymes?

A

Organic groups attached to enzyme that are necessary for its operation

23
Q

Which reaction produces GTP?

A

Succinyl-CoA to succinate

24
Q

What % of LSE groups smoke?

A

65%

25
Q

Which amino acid can have a urea molecule cleaved from it?

A

Arginine

26
Q

What is main source of glucose in the blood 8 hours after a high carbohydrate meal?

A

Glycogenolysis

27
Q

Which steps of glycolysis synthesise ATP?

A

3-biphosphoglycerate –> 3-phosphoglycerate

phosphenol pyruvate –> pyruvate

28
Q

Which steps of glycolysis use ATP?

A

Glucose –> glucose-6-phosphate

Fructose-6-phosphate –> fructose-1,6-biphosphate

29
Q

What are the cofactors of the link reaction?

A

NAD+, thiamine pyrophosphate, lipoic acid, FAD, coenzyme A

30
Q

How much energy is in 1g of fat?

A

38 kJ (9 cals)

31
Q

What can fitness be defined as?

A

Endurance, strength, balance, coordination and flexibility

32
Q

How much does passive smoking increase miscarriage risk?

A

25%

33
Q

What is the daily recommended intake of protein?

A

50-70g

34
Q

What is formed from splitting fructose-1,6-biphosphate?

A

Glyceraldehyde-3-phosphate and dihydroxyacetone phosphate

35
Q

What is the average fasting blood glucose?

A

4.5 mM

36
Q

What is annual cost of alcohol misuse to NHS?

A

£3 billion

37
Q

What is oxidation in the TCA cycle coupled to?

A

Reduction of NAD+

38
Q

What happens in stage 4 of B-oxidation?

A

Removal of 2C using B-ketoacidCoA-thiolase

39
Q

How many ATP are produced per turn of TCA cycle?

A

10

40
Q

What is the reaction type of enoyl-CoA conversion to 3L hydroxyacyl CoA?

A

Hydration

41
Q

What % of deaths in people aged 35-70 are caused by tobacco?

A

30%

42
Q

What controls phosphofructokinase allosterically and inhibit it?

A

ATP and citrate

43
Q

What kind of glucose must be used in glycolysis?

A

D-glucose

44
Q

What is the reaction type of fatty acid conversion to enoyl-CoA?

A

Oxidation

45
Q

What is the first reaction of glycolysis?

A

Glucose to glucose-6-phosphate

46
Q

What is the daily protein turnover?

A

300-400g per day

47
Q

What kind of enzyme is a lipase?

A

Hydrolase

48
Q

What increases protein breakdown?

A

Starvation, cortisol

49
Q

How much does heavy smoking increase the risk of death under 45 due to coronary heart diease?

A

15 x

50
Q

How much energy is release from conversion of ADP to ATP?

A

30 kJmol-1

51
Q

What is glucose used for in adipose tissue?

A

Glycerol production

52
Q

How many glucose residues are there between branching points on glycogen?

A

10

53
Q

How are fatty acids activated?

A

By combination with CoA using energy from ATP = AMP + 2Pi

54
Q

What kind of diseases are glycogen storage diseases?

A

Autosomal recessive

55
Q

What is a plasma glucose level of 6.5 mM?

A

Normal for fed state

56
Q

What does DNA and RNA breakdown produce?

A

Uric acid

57
Q

What is the second reaction of glycolysis?

A

Glucose-6-phosphate to fructose-6-phosphate

58
Q

What stimulates glucagon release?

A

Hypoglycaemia, adreniline acting on b2, a1, a2 receptors, acetylcholine, CCK

59
Q

How does the production of lactate allow glycolysis to continue in anaerobic conditions?

A

NADH is oxidised back to NAD+ in lactate formation

60
Q

How does glycerol travel in the blood?

A

Freely

61
Q

How can malate be converted to pyruvate?

A

Via malic enzyme

62
Q

What does transamination of oxaloacetate produce?

A

Aspartate

63
Q

What is favism disease?

A

Glucose-6-phosphatase deficiency

64
Q

Which enzyme incorparates an amino acid into an orthine group in the urea cycle?

A

Orthinine transcarbamoylase

65
Q

How many NADH are formed from glycolysis of one glucose molecule?

A

2NADH

66
Q

Why would a reaction in a metabolic pathway be irreversible?

A

The equilibrium overwhelmingly favours the forward reaction

67
Q

What is glucose made from in gluconegenesis?

A

Glycerol and some keto acids

68
Q

What breaks old or damaged proteins down?

A

The ubiquitin system

69
Q

Which enzyme catalyses the second reaction of glycolysis?

A

Phosphoglucose isomerase

70
Q

What happens in stage 2 of B-oxidation?

A

Addition of H2O using enoyl-CoA-hydratase

71
Q

How do free fatty acids travel in blood?

A

Bound to albumin

72
Q

What group smoke most?

A

Middle aged men

73
Q

What allows amino acids to be converted to one another via transaminiaton?

A

The presence of pyridoxal phosphate

74
Q

How many ATP are produced per NADH?

A

2.5

75
Q

What is McArdle’s disease?

A

Myophosphorylase deficiency so cannot break down glycogen into glucose for muscle. Causes exercise intolerance.

76
Q

Which enzyme catalyses the first reaction of glycolysis?

A

Hexokinase

77
Q

What does aldolase do?

A

Split fructose-1,6-biphosphate

78
Q

How many NADH and FADH are formed from one round of B-oxidation?

A

1 of each

79
Q

What is most effective stop smoking plan?

A

Group therapy and medication

80
Q

What is main source of glucose in the blood 24 hours after a high carbohydrate meal?

A

Gluconegenesis

81
Q

How are amino acids from degraded muscle protein transported in the blood?

A

As part of glutamine after combination with glutamate

82
Q

What happens in stage 1 of B-oxidation?

A

Removal of 2H using acetyl-CoA-dehydrogenase

83
Q

What is the reaction type of conversion of B-ketoacyl CoA to fatty acid acyl CoA and acetyl CoA?

A

Thiolysis

84
Q

What happens to glyceraldehyde-3-phosphate in glycolysis?

A

It is oxidised and phosphorylated

85
Q

How can oxaloacetate be converted to phosphoenol pyruvate?

A

Via PEP carboxylase

86
Q

What is pyruvate converted to in the first step of gluconegenesis?

A

Oxoacetate

87
Q

Which molecules are oxidised in the TCA cycle?

A

Isocitrate, a-ketoglutarate, succinate, malate

88
Q

Which hormone promotes glycolysis and when?

A

Glucagon in the fasting state

89
Q

How can fructose enter glycolysis?

A

By conversion to fructose-1-phosphate by fructokinase

90
Q

What inhibits glucagon release?

A

Somatostatin, insulin, free fatty acids, ketoacids, urea

91
Q

What activates glycogen phosphorylase?

A

Phosphorylation

92
Q

What % of coronary heart disease deaths are due to smoking?

A

20%

93
Q

What usually accepts the amino group in transamination?

A

2-oxoglutarate

94
Q

Which amino acid can be deaminated to remove an ammonia group?

A

Glutamate

95
Q

What happens in stage 3 of B-oxidation?

A

Removal of 2H using 3-hydroxyacylCoA-dehydrogenase

96
Q

What are the enzymes of the irreversible reactions of glycolysis?

A

Hexokinase, phosphofructokinase and pyruvate kinase

97
Q

What is the penultimate reaction of glycolysis and what enzyme is used?

A

Dehydration of 2-phosphoglycerate via endolase

98
Q

What oxidises molecules in the TCA cycle?

A

Dehydrogenases

99
Q

How are amino acids from degraded proteins excreted?

A

As urea and ammonium ions

100
Q

What is the reaction type of 3L hydroxyacyl CoA conversion to B-ketoacyl CoA?

A

Oxidation

101
Q

What is formed from metabolism of ketogenic amino acids?

A

Pyruvate —-> glucose or CO2 and H2O

102
Q

What are the 4 stages of glycolysis?

A

Activation, splitting of 6C sugar, oxidation, ATP synthesis

103
Q

What cofactor is used in protein synthesis?

A

GTP

104
Q

What % of adults currently smoke?

A

20%

105
Q

How much does smoking decrease life expectancy?

A

10 years