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Flashcards in glycogen degradation Deck (99):
1

what are chains of glucose connected by

a(1-4)

2

what are branches of glucose connected by

a(1-6)

3

how often does branching occur

every 10 glucose molecules

4

what does branching provide

increased solubility
easier access to glucose

5

maltose is a

a(1-4)

6

what the size of most granules

mid size

7

whats the maximal size of glucose molecules

55000

8

how many tiers of a carb

12

9

what does carb density increase

exponetially with each tier
non reducing ends
34.6% of the total glucose are in the outer tier

10

what are more sensitive to dietary carbs

proglycogen

11

what are synthesized more rapidly following post exercise glycogen depletion reaching a plateau after 24 hours

proglycogen

12

what builds fast but is smaller

proglycogen

13

what is slower and more constant

macroglycogen

14

what synthesis can last for 48 hours post exercise

marcogylcogen

15

what is responsible for carb loading

macroglycogen

16

what cannot release glucose

skeletal muscle

17

what can release glucose

liver

18

what stores glycogen but in small qyanitities

other cells

19

what lacks an enzyme to release glucose

muscle

20

what is the cellular location of glycogen

cytosol

21

phosphorylate glucose

hexokinase and glucokinase

22

make UDP glucose

UTP utilization
pyrophosphatase

23

initiation glycogen synthesis

connect glucose to glcogenin

24

elongation of the chain in glycogen synthesis

glycogen synthesis adds glucoses

25

branching in glycogen synthesis

4:6 transfer

26

what is a protein that starts the glycogen chain with the amino acid tyrosine

glycogenin

27

what is the initiation enzyme

glycogen initiator synthase

28

what is 1 ATP broken down to make

glucose 6 phosphate

29

what it UTP broken down to create

UDP glucose

30

what is pyrophosphate broken down to create

UDP glucose

31

what happens when you are resynthesizing glycogen

you are using ATP

32

what is the equivalence of 3 ATPs broken down

to attach each glucose

33

glucose synthase has what bonds

a(1-4)

34

elongation of the chain is done by what enzyme by adding glucose molecules

glycogen synthase

35

branching occurs by what enzyme

glucosyl 4:6 transferase

36

glucosyl 4:6 transferase has what bond

a(1-6)

37

what type of carbon chain are taken from the end and attached to another glucose molecule in the chain

5:8

38

what kind of bond can glycogen synthase add

a(1-4)

39

what bond can be added to additional growing chains

a(1-6) by 4:6 transferase

40

what is the result of adding a(1-4) bonds and a(1-6) bonds

highly branched structure

41

what are the two main enzymes of regulation

glycogen synthase
glycogen phosphorylase

42

low atp
lots of ADP AMP
low glucose
glucagon
muscle contraction

glycogen phosphosylase

43

lots of ATP
lots of glucose
insulin
low glycogen levels

glycogen synthase

44

what is glycogen synthase a key enzyme responsible for

synthesis of glycogen

45

muscle glycogen concentration is a far more potent regulator of glycogen synthase activity then what

insulin or muscle contraction

46

what is glycogen synthase bound to a part of

glycogen protein complex

47

what happens when the concentration of glycogen decreases

glycogen synthase is released

48

what is the most potent stimulator of glycogen synthase

glycogen levels within the muscle

49

what does intense exercise burn

muscle and liver glycogen

50

what does exercise do

Glut 4 translocation
Glut 4 transcription-translation (more transporters)

51

what happens post exercise

stimulates glycogen synthesis (free glycogen synthase)
increases insulin sensitivity

52

what type of fiber is responsible for more hypertrophy

TYPE II

53

what happens after intense exercise

glycogen synthesis has an initial high rate
maximal activity during the first 30 min
rapid decline to about 1/5 by 60 min
reduced by 1/9 by 120min

54

what are two reasons for the decline after intense exercise

increased glucose uptake (gluts 4)
increased glycogen enzyme activity (glycogen synthase)

55

the rapid phase is what

insulin independent
occurs when glycogen levels are relatively low and carbs are provided quick after exercise
30-60 min

56

the slow phase what happens

several hours later
insulin dependent
much slower rate of glycogen synthesis
must had carbs and insulin availible

57

where is glycogen primarily stored

liver and skeletal muscle

58

what happens to glycogen synthase after high glycemic carbs are consumed after exercise

the resaultant hyperinsulinemia leads to only a slight increase of glycogen synthase

59

by adding carbs it will increase insulin but what will it not have an effect on

no additive effect on glycogen synthase

60

what happens two hours post exercise to the number of glucose transporters associated with the sarcolemma

it returns to the pre exercise concentration

61

what may be 45% lower when carb ingestion post exercise is delayed by 2 hours compared with immediate consumption post exercsise

muscle glycogen synthesis rates lower

62

what does consuming carbs after exercise increase

increase glycogen synthesis

63

what does it meant when you do not consume carbs after exercise but are still able to build glycogen

you are catabolizing amino acids to make glycogen

64

T/F
CHO supplements provided at 2 hour interval may not adequately increase and maintain blood glucose and insulin levels for 2 hours

true

65

by ingestion of carbs and proteins after exercise what happens in comparison to just ingesting carbs alone

it leads to a higher muscle glycogen synthesis rate

66

when intaking a high amount of carbs and some proteins what will happen

it will not lead to a higher glycogen synthesis in comparison with just intaking small amounts of both carbs and proteins together

67

what different types of proteins impact muscle glycogen levels
(faster to slower)

1) whey protein hydrosylates
2) whey protein
3) casein hydrosylates
4) brain chain amino acids

68

do trained or untrained have a higher increase in glycogen storage

trained have a 2 fold higher increase

69

what is the better teh quality of the carb or the quantity of the carb in GI?

the quality is better

70

the higher the glycemic load the greater the expected elevation in blood glucose and in the insulinogenic effect of food
T/F

T

71

what is glycemic load

the glycemic index times the grams of carbs in a serving of the food

72

what is long term consumption of a diet with a relative high glycemic load associated with

associated with an increased risk of type 2 diabetes and coronary heart disease

73

the longer and higher the elevation of blood glucose the greater the risk for what

developing chronic disease and obesity

74

what are high GI meals more effective at replenishing muscle glycogen stores during what phase of recovery

the second phase
allows a faster not better repletion

75

what does low insulin during exercise allow

allows a increased in FFA concentration

76

blood glucose levels tend to be higher in the later phase of prolonged exercise when subjects are fed what

low GI compared with high GI pre exercise meals

77

what happens to insulin regardless of what you consume before you exercise

insulin levels decrease and reach the same values regardless of the GI of the pre exercise meal

78

glucose and glucose/fructose solutions ingested at a rate of 90g/h are equally effective at what

restoring muscle glycogen in exercise muscles during the recovery from exhaustive exercise

79

why is fructose thought to mediate this effectof very low doses of fructose are added to a glucose containing meal glucose tolerance is improved

activating glucokinase

80

low dose fructose infusion cause a 3 fold increase in net hepatic glycogen synthesis exclusively through

stimulation of glycogen synthase flux

81

what has a higher Km which takes more glucose to get it going

glucokinase

82

what is not inhibited by glucose 6 phosphate which keeps going

glucokinase

83

what is stimulated by insulin and fructose

glucokinase

84

what is inhibted by G6P

hexokinase

85

what do low doses of fructose cause a 3 fold increase in

liver glycogen synthesis

86

what do small amounts of fructose cause a release of

glucokinase from a regulatory protein

87

F6P binds to a regulatory protein and inhibits

glucokinase

88

when F1P binds to a regulatory protein what is set free and activated

glucokinase

89

what is the main endogenous source of glucose

the liver is the fasted state

90

following glucose consumption what consumes it

the liver along with removing 1/3 of an oral carb load

91

what will not cause the liver to take in glucose when blood glucose is in the normal range

insulin

92

what is the primary site of fructose disposal

the liver is 70% total

93

what enzymes are essential for fructose metabolism ana are highly expressed in the liver

fructokinase
triokinase (limited expression in muscle and adipose tissue)

94

why are high levels of fructose not good

liver has high uptake
increased fat lactate and glycerol formation

95

what are relatively the same

HFCS and sucrose

96

what has no benefit for muscle glycogen synthesis

fructose

97

what low doses increase liver glycogen synthesis

fructose

98

glycogen regulation synthesis

1) high blood glucose
2) insulin
3) fructose
4) low glycogen content
5) high energy charge
6) ATP

99

glycogen regulation breakdown

1) low blood glucose
2) glucagon
3) low energy charge
4) ADP AMP
5) calcium