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Flashcards in Biochem 2 Deck (96):
1

Which type of fatty acid predominates olive oil?

Long chain (C16, C18) monosaturated fatty acids

2

What are polyunsaturated fatty acids

Acids which have 2 or more double bonds in the their structure.
Cis conformation

3

What is the cis conformation?

Normal configuration.
Molecules pack less tightly together so the melting point is reduced.

4

What are the components of a triacylglyerol?

Glycerol
3 fatty acids

5

What form are plant oils at room temperature? Why?

Liquid. They contain a high proportion of unsaturated fatty acids

6

What are the properties of a triacylglyerol with high saponification value?

Contains a high proportion of short chain fatty acids

7

What is a saponification value

Mg of KOH required to saponify 1g of oil or fat

8

What is iodine number

G of iodine which will combine with 100g of oil or fat

9

What type of bond forms when an alcohol reacts with a carboxylic acid?

Ester bond

10

Which process allows transport of a solute from one side of a biological membrane to the other?

Diffusion

11

What is amphipathic

A compound which contains one polar region and one non- polar region.

12

How many moles of ATP are produces when the acyl group of a C14 fatty acyl coA is oxidised

114

13

What catalyses the addition of carbon dioxide to acetyl coA

Fatty acyl coA synthase

14

What is formed from co3 and acetyl coA at the start of the fatty acid synthesis pathway

Malonyl coA

15

What compound is the last compound which is common in the synthesis of both TAG and PAG

Phosphatidate

16

Where does B oxidation take place in animal cells?

Mitochondria

17

What is glycerol activated to before the synthesis of TAG Or PAG

Glycerol-3-phosphate

18

What vitamin is required by the enzyme acetyl coA carboxylase for the carboxylation of acetyl coA before the malonyl pathway?

Biotin

19

What is the order of the reactions in the malonyl pathway?

Joining
Reduction
Dehydration
Reduction

20

What is used as the hydrogen donor in the maonyl pathway?

NADPH+H+

21

Which processes are associated with photosystem 2 in photosynthesis in plants?

Photo-oxidation
Photophosphorylation

22

Where does the light reactions of photosynthesis take place?

Thylakoid membrane

23

Which enzyme is responsible for the carboxylation reaction in the dark reactions of photosynthesis?

Ribulose-bisphosphate carboxylate (RUBISCO)

24

What are the primary electron acceptors in PSI and PSII

Fx
Pheophytin

25

What are the final products of photosynthesis and formed in the light reactions of photosynthesis

Oxygen

26

What compound is the starting and ending point for the cyclic reactions in the dark reactions of photosynthesis?

Ribulose-1,5-bisphosphate

27

What is the name of the cytochrome complex in the photosynthetic electron transport chain in which two cytochromes are involved in?

Cytochrome bf complex

28

What are the most important light sensitive pigments involved in photosynthesis?

Chlorophyll

29

During gluconeogenesis, conversion between _____ and ______ required two reactions whereas the reverse in glycolysis only requires one reaction

Pyruvate
Phosphoenol pyruvate (PEP)

30

Which compounds can be used as substrates for gluconeogenesis in most organisms?

Pyruvate
Oxaloacetate
Glyceradehyde-3-phosphate

31

Which pathway can glucose be synthesised from pyruvate?

Gluconeogenesis

32

Which proteins combine to form the enzyme lactose synthase in the mammary gland?

a-lactalbumin
Galactosyl transferase

33

What is true about glycogen synthase?

Its activity is increased by insulin
It is activated by removal of a phosphate group from its structure

34

Which compounds react together in the reaction catalysed by sucrose phosphate synthase?

Fructose-6-phosphate
UDP-glucose

35

In the glyoxylate cycle the enzyme isocitrate lyase converts isocitrate to glyoxylate and ______

Succinate

36

What compound does the enzyme pyruvate carboxylase convert pyruvate to

Oxaloacetate

37

What process used for ammonia assimilation requires energy?

Gluatmine synthetase (GS)

38

Which amino acids are part of the urea cycle but never found in proteins?

Ornithine
Citrulline

39

What is the process by which plants are able to synthesise all the amino acids they require from gluatmic acid (glutamate) and keto acids

Transamination

40

What is the process by which ammonia is converted to the amino acid glutamic acid

Ammonia assimilation

41

How many atoms of nitrogen are excreted in one molecule of urea?

2

42

Which enzymes are required to convert nitrogen gas into ammonia?

Nitrogenase reductase
Nitrogenase

43

What are the components of a phosphoacylglycerol (phospholipid)?

Glycerol
2 fatty acids
Choline, inositol, ethanolamine or serine
Phosphate

44

What enzymes release fatty acids from triacylglycerols?

Lipases

45

What type of pathway is the urea cycle?

Energy requiring pathway

46

What type of bonds to cellulose and starch synthase molecules form?

Cellulose- B1-4 glycosidic bond
Glycogen/Statch- a1-4 glycosidic bond

47

Before synthesis of TAGs or PAGs can take place, glycerol is first activated to _______

Glycerol-3-phosphate

48

Why must the light reactions precede the dark reactions of photosynthesis?

Because the ATP and NADPH produced in the former are used in the latter

49

How many c atoms does isocitrate contain?

6

50

How many c atoms does 2-oxo-glutarate contain?

5

51

How many c atoms does malate contain

4

52

How many c atoms does glyoxylate contain

2

53

Why is the conversion of pyruvate to ethanol irreversible?

Because carbon dioxide is released in the first part of reaction

54

What is the fatty acid type that predominates in cod liver oil?

Very long chain (>C18) polyunsaturated fatty acids

55

What is the process by which ammonia is converted to the amino acid glutamic acid

Ammonia assmilation

56

Which coenzymes/cofactors are involved in the reactions which convert pyruvate to acetyl coA and 2-oxo-glutarate to succinyl coA

Mg2+
CoA
FAD
NAD+
Lipoic acid
TPP

57

Which enzymes are required to convert nitrogen gas to ammonia?

Nitrogenase reductase
Nitrogenase

58

Which enzyme catalyses the only true oxidation reaction?

Glyceraldehyde-3-phosphate dehydrogenase

59

How many double bonds does stearic acid have

0

60

How many double bonds does oleic acid have

1

61

How many double bonds does linoleic acid have?

2

62

How many double bonds does linolenic acid have?

3

63

What process used for ammonia assimilation requires energy?

Gluatmine synthetase (GS)

64

Which amino acids are part of the urea cycle but never found in proteins?

Ornithine
Citrulline

65

What is the process by which plants are able to synthesise all the amino acids they require from gluatmic acid (glutamate) and keto acids

Transamination

66

What is the process by which ammonia is converted to the amino acid glutamic acid

Ammonia assimilation

67

How many atoms of nitrogen are excreted in one molecule of urea?

2

68

Which enzymes are required to convert nitrogen gas into ammonia?

Nitrogenase reductase
Nitrogenase

69

What are the components of a phosphoacylglycerol (phospholipid)?

Glycerol
2 fatty acids
Choline, inositol, ethanolamine or serine
Phosphate

70

What enzymes release fatty acids from triacylglycerols?

Lipases

71

What type of pathway is the urea cycle?

Energy requiring pathway

72

What type of bonds to cellulose and starch synthase molecules form?

Cellulose- B1-4 glycosidic bond
Glycogen/Statch- a1-4 glycosidic bond

73

Before synthesis of TAGs or PAGs can take place, glycerol is first activated to _______

Glycerol-3-phosphate

74

Why must the light reactions precede the dark reactions of photosynthesis?

Because the ATP and NADPH produced in the former are used in the latter

75

How many c atoms does isocitrate contain?

6

76

How many c atoms does 2-oxo-glutarate contain?

5

77

How many c atoms does malate contain

4

78

How many c atoms does glyoxylate contain

2

79

Why is the conversion of pyruvate to ethanol irreversible?

Because carbon dioxide is released in the first part of reaction

80

What is the fatty acid type that predominates in cod liver oil?

Very long chain (>C18) polyunsaturated fatty acids

81

What is the process by which ammonia is converted to the amino acid glutamic acid

Ammonia assmilation

82

Which coenzymes/cofactors are involved in the reactions which convert pyruvate to acetyl coA and 2-oxo-glutarate to succinyl coA

Mg2+
CoA
FAD
NAD+
Lipoic acid
TPP

83

Which enzymes are required to convert nitrogen gas to ammonia?

Nitrogenase reductase
Nitrogenase

84

Which enzyme catalyses the only true oxidation reaction?

Glyceraldehyde-3-phosphate dehydrogenase

85

How many double bonds does stearic acid have

0

86

How many double bonds does oleic acid have

1

87

How many double bonds does linoleic acid have?

2

88

How many double bonds does linolenic acid have?

3

89

Transketolase

Requires TPP as a coenzyme and Mg2+ as a cofactor.
Takes 2C unit from the top of a ketose and adds it to an aldose

90

Transaldolas

Takes a 3C unit from the top of a ketose and adds it to an aldolase

91

What compounds are produced at the end of the non oxidative phase of the phosphate pathway and feed into glycolysis?

Glyceraldehyde-3-phosphate
Fructose-6-phosphate

92

What enzyme catalyses the addition of CO2 to acetly coA to form malonyl coA at the start of the fatty acid synthesis pathway?

Acetyl coA carboxylase

93

What enzyme catalyses the conversion of pyruvate to acetyl coA?

Pyruvate dehydrogenase

94

Amphipathic molecule?

Molecule with one polar region and one non polar region

95

ATP is produced during photosynthesis by what process?

Photophosphorylation

96

What bond is formed when an alcohol reacts with a carboxylic acid

Ester