Exam 3 #2 Flashcards Preview

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Flashcards in Exam 3 #2 Deck (105):
1

Reactions that any cell used to acquire, store or use energy.

Metabolism

2

Multiple incoming pathways

convergent

3

multiple outgoing pathway forks

divergent

4

sets of individual reactions, grouped together, to produce a final product

metabolic pathways

5

groups of metabolic enzymes that are close by each other. Held together by non-covalent interactions.

metabolons

6

what works by channeling the product of one catalyzed reaction from the active site of one enzyme directly to the active site of the next enzyme

metabolons

7

2 sub paths of metabolism

catabolism and anabolism

8

amino acids, monosaccharides, and fatty acids involves oxidizing carbon.

catabolism (breaks down)

9

amino acids, monosaccharides, and fatty acids involves reducing carbon

anabolism (builds up)

10

what are linked via ATP

Catabolism (produces energy)
Anabolism (consumes energy)

11

Metabolism Summary

Metabolic pathways are all connected.
Pathway activity is regulated.
Not every cell carries out every pathway.

12

Delta G < 0

energy is released

13

Delta G = 0

equilibrium

14

Delta G > 0

energy is required

15

Net reaction of Glycolysis

Glucose + 2 NAD + 2 ADP + 2 Pi -> 2 Pyruvate + 2 NADH + 2 H + 2 ATP

16

Cellulose, Amylase
Starch, Glycogen converted to glucose

Polysaccharides

17

Maltose, Sucrose, Lactose

Disaccharides

18

Glycolysis

is a central pathway

19

Pyruvate moves on to the Krebs cycle in

aerobic conditions

20

Pyruvate can not be oxidized so it can't go to CO2 in

anaerobic conditions

21

Lactate can be converted back to pyruvate by lactate dehydrogenase or to glucose via

gluconeogenesis

22

lactate dehydrogenase is a

bidirectional enzyme

23

The process of making glucose from molecules other than carbohydrates is called

gluconeogenesis

24

Metabolites are toxic if levels build up too high. what allows us to have low levels of metabolites

metabolon

25

Each phosphoanhydride bond contains

30.5 kJ/mol to form and break bonds

26

Delta G that is Negative is

Spontaneous

27

Negative Delta G Products are favored over

reactants

28

What steps in glycolysis are not reversible

1, 3, 10

29

What is the gate keeper of the Krebs Cycle

pyruvate dehydrogenase

30

What is activated by high levels of ATP, Acetyl-CoA, NADH. active

Pyruvate dehydrogenase kinase

31

What is stimulated by low concentrations of ATP, Acetyl-CoA, and NADH. Self regulated

Pyruvate dehydrogenase phosphatase

32

What are the three enzymes in the Krebs cycle that are unidirectional

Citrate synthase, Isocitrate dehydrogenase, alpha ketoglutarate

33

What is inhibited by high levels of NADH, Citrate, Succinyl-CoA, and ATP. Stimulated by ADP.

Citrate Synthase

34

What inhibits synthesis if levels are too high

Succinyl-CoA

35

What is inhibited by ATP but stimulated by ADP

Isocitrate dehydrognease

36

What is inhibited by succinyl-CoA and NADH. Not stimulated by anything.

alpha ketoglutarate dehydrogenase

37

Where is pyruvate produced

in the cytoplasm

38

Pyruvate is moved into the inner matrix of the mitochondria by

an anti-port

39

Pyruvate has what charge

negative

40

Oxidation of pyruvate and the enzymes that catalyze these reactions are found inside the

mitochondria

41

What process is the gatekeeper of aerobic metabolism and is critical to life

pyruvate being converted to acetyl-CoA

42

Reactions that produce the molecules that replenish the Krebs cycle are called

Anaplerotic reactions

43

Low levels of high energy molecules act to _____ activity of Krebs cycle enzymes

increase

44

High levels of high energy molecules act to _____ activity of Krebs cycle enzymes

decrease

45

Glyoxylate Cycle is similar to the Krebs cycle except that isocitrate is borken down to

succinate and glyoxylate

46

Succinate is used in gluconeogenesis to make

carbohydrates

47

Energy can be harvested by transfer of Hydrogen to O2 by

Oxidative phosphorylation

48

Enzymes called dehydrogenase

catalyze reactions

49

Electrons spontaneously flow from the molecule with the highest reductive potential to one with a lower reductive potential.

Oxidation-reduction

50

Energy released during electron transport is captured by

ATP formation

51

What is the most powerful reducing agent

NADH

52

Integral membrane proteins bound in the inner membrane of mitochondria that had 26 protein subunits. NADH and H -> FMN

Complex I (NADH)

53

what is reduced by accepting electrons

FMN

54

Coenzyme Q is

ubinquinone

55

Electrons flow from initial carrier to FAD

Complex II (Succinate)

56

Accepts electrons from ubiquinone via intermediates such as cytochromes in what complex

Complex III (Cytochrome c)

57

Consists of 10 protein subunits. Cytochormes which contain heme

Complex IV

58

In what complexes are H ions pumped out

Complex I, II, IV

59

Brown adipose tissue has a lot of

mitochondria

60

Hibernating bear

ATP not produced even when electron transport chain is active. Energy is released via heat

61

Electron transport is uncoupled from ATP synthesis because bear fat cells have extra pores in mitochondrial membrans

Thermogenin or the uncoupling protein

62

Oxidation of Glucose yields how many ATP

36 ATP

63

Carbohydrates are stored in

water

64

Triacylglycerols are stored without

water

65

Fatty acids end up being metabolized to

Acetyl-CoA

66

Triacylglycerols are

digested

67

What enzyme cleaves the acyl chains off of the triacylglycerols

lipases

68

What are made up of triacylglycerols, cholesterol, phospholipids, and lipoproteins. and can be passed into the bloodstream.

Chylomicrons

69

Triacylglycerols can be releaed from chylomicrons by an enzyme known as

lipoprotein lipase

70

What are stored and told when to release the fatty acids they are stored in.

adipocytes

71

Hormones such as ______ and ______ are blood borne signals for adipocytes to cleave fatty acids from triacylglycerols and release the fatty acids into the bloodstream

epinephrine and glucagon

72

Fatty acids are delivered to the muscle cells by

albumin

73

transport protein for acyl carnitine via passive transport

acyl carnitine transferase

74

B oxidation takes place in the

mitochondrial matrix

75

Found in the mitochondrial matrix, is a central molecules in fatty acid synthesis and is converted to citrate

Acetyl-CoA

76

Can be transported to the cytoplasm and can be converted back to oxaloacetate and acetyl-CoA in the cytoplasm

Citrate

77

What is used as feedback to make fatty acids

Acetyl-CoA

78

Acyl carrier protein (ACP) is bound by a

thioester bond

79

The only thing made from fatty acid synthase is

palmitite acids

80

What stimulate fatty acid synthase and is a positive regulator of fatty acid synthase.

Citrate

81

Increased amount of _____ turns on fatty acid synthase

Citrate

82

Palmitoyl CoA inhibits

Acetyl-CoA Carboxylase

83

triacylglycerols from liver to tissues

very low density lipoproteins VLDL

84

High levels of Cholesterol. bad cholesterol

LDL

85

lower levels of cholesterol. free cholesterol

HDL

86

Glycolysis, Krebs cycle, fatty acid metabolism

Catabolism

87

gluconeogenesis and fatty acid synthesis

Anabolism

88

What links glycolysis with glycogen storage and intake of dietary carbohydrates

G6P

89

What links glycolysis to gluconeogenesis with the Krebs cycle

Pyruvate

90

under anaerobic conditions

glycolysis and fermentation

91

under aerobic conditions

Krebs cycle

92

What links the Krebs cycle to pyruvate and fatty acid B oxidation and fatty acid synthesis

Acetyl-CoA (the most central molecule)

93

What links Krebs cycle to gluconeogenesis

Oxalacetate

94

Fatty acid synthesis happens in the

cytosol

95

B oxidation happens in the

mitochondrial matrix

96

What transfers energy from the liver to the muscle during anaerobic metabolism

Cori Cycle

97

What are extracellular signals that are produced by endocrine glands, carries in the blood and received by specific cells

Hormones

98

What turns on glycogen synthesis and glycolysis and turns off glycogen breakdown when glucose levels are high

Insulin

99

What turns on glycogen breakdown when glucose levels are low

Glucagon

100

Dephosphorylated Glycogen Synthase is

more active

101

Dephosphorylated Glycogen phosphorylase is

less active

102

phosphorylated Glycogen Synthase is

less active

103

phosphorylated Glycogen phosphorylase is

more active

104

What turns on lipases and glycogen phosphorylase to release fatty acids from triacylglycerols and glucose release from glycogen

Epinephrine

105

In glycolysis, NADH is increased. The Krebs cycle is inhibited by 2 enzymes. If inhibited then Acetyl-CoA builds up then pyruvate builds up but pyruvate cant build up it turns to

Lactate. Increased levels of lactic acid will cause cells to denature and cause a conformational change.