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Flashcards in Glycogen degradation exam 2 Deck (32):
0

Glucose's energy source for?

Brain
Blood cells
Exercising muscles

1

Glucose sources?

Diet glycogen gluconeogenesis

2

Gluconeogenesis

Synthesis of glucose
Slow response

3

Glycogen and low blood sugar

Glycogen in liver and kidney can breakdown and release glucose quickly

4

Glycogen and exercising muscle

Glycogen in muscle can breakdown and release glucose for energy

5

Glycogen primary sites for storage

Liver and skeletal muscle

6

Chains of glucose are connected by what glycosidic bonds?

A (1-4)

7

Branch points are formed by what glycosidic bonds

A(1-6)

Occurs every 10 glucose molecules
Increased solubility
Easier access to glucose

8

Where is glycogen stored

Cytosol

9

Glycogen to glucose 1 phosphate what enzyme and coenzyme is used

Glycogen phosphorylase and pyridoxal phosphate

10

Mutation phase

Glucose 1 phosphate converted to glucose 6 phosphate by phosphoglucomutase

11

T/F muscles lack the enzyme needed to release glucose

True

12

Glucose 6 phosphate and the liver

Converted to free glucose (g6p)
ER
Glucose sent to cytosol (released in the blood stream)

13

G6P and the muscles

Glycolysis

14

Is phosphorylase still effective at breaking down glycogen?

No

15

How many glucose molecules have to be left in order for glycogen breaking down to stop proceeding?

4

16

What are the enzymes required in order to break down the branches?

Glucosyl (4:4) transferase removes 3 outer glucose molecules
Amylo a(1 6) glucosidase removed the last glucose branch

17

When does glycogen phosphorylase begin again

After it gets four away from the last branch

18

Glycogenolysis regulation main enzyme?

Glycogen phosphorylase

19

Glycogenolysis regulation in the liver is

Fasting stimulating

20

Glycogenolysis in the muscle is

Stimulated during exercise

21

Glycogenolysis regulation and hormones

Glucagon (liver)
Epinephrine (liver muscle)

22

Activation of adenylyl cyclase

Camp
Protein kinase a PKA

23

Glycogen regulation is broken down by what

Calcium (muscle contraction)
Epinephrine
Low energy charge
Low blood glucose (glucagon)
ADP AMP

24

Calcium is released where and binds to what

Released in muscle (neural stimulation) and liver (epinephrine)
Binds to calmodulin (caM) Ca2+-CaM complex

25

What does calmodulin activate

Phosphorylase kinase

26

Ca+ and energy charge

Muscle contraction uses ATP
Neural stimulation releases Ca2+ from SR. (which binds to CaM)

27

Ca2+ and stress

Liver
Epinephrine released from adrenal medulla (need glucose)
Releases Ca2+ from ER to cytoplasm and binds to CaM

28

AMP and energy charge

Muscle
High levels of AMP
AMP binds to glycogen phosphorylase b (no phosphorylation)

29

Glycogen phosphorylase

Low ATP
High levels of ADP AMP
Low levels of glucose
Glucagon (liver)
Muscle contraction (calcium)

30

Glycogen synthase

Lots of ATP
High levels of glucose
Insulin
Low glucagon levels

31

Enzymes for glycogen breakdown

Glycogen phosphorylase
Phosphoglucomutase
Glycosyl (4:4) transferase
Amylo a (1 6) glucosidase
Glucose 6 phosphate