Glycogen

Question 1

What are the Energy sources of glucose?

Answer 1

brain, blood cells, exercising muscle

Question 2

What are our sources of glucose?

Answer 2

Diet
glycogen
gluconeougenesis

Question 3

How quickly does Gluconeogenesis respond when glucose is needed?

Answer 3

it has a slow response

Question 4

What can glycogen do when we have low blood sugar?

Answer 4

glycogen in liver and kidney can breakdown and release glyucose quickly

Question 5

what can glycogen do in exercising muscle?

Answer 5

glycogen in muscle can breakdown and release glucose for energy

Question 6

What is the storage form of carbohydrates in humans?

Answer 6

glycogen

Question 7

What kind of bonds does Maltose contain?

Answer 7

alpha(1->4) Bond between two glucose molecules

Question 8

What are the primary storage sites of Glycogen?

Answer 8

liver and skeletal muscle

Question 9

What forms the chains in glycogen?

Answer 9

alpha (1->4) bonds (a glycosidic bond)

Question 10

What kind of are the branch points in glycogen?

Answer 10

alpha(1->6) bonds (a glycosidic bond)

Question 11

What bonds does glycogen contain?

Answer 11

branched are alpha (1->6)

chains are alpha(1->4) bonds

Question 12

when does branching occur in glycogen?

Answer 12

approximately every 10 glucose molecule

Question 13

What is the purpose of branching in glycogen?

Answer 13

provides increased solubility

provides easier access to glucose

Question 14

What is the cellular location of glycogen?

Answer 14

the cytosol

Question 15

How do we convert glycogen into Glucose-1-phosphate?

Answer 15

with glycogen phosphorylase and coenzyme-pyridoxal phosphate

Question 16

What is the product of this reaction: Glycogen —-Glycogen phosphorylase+ Coenzyme-pyridoxal phosphate –> ???????????

Answer 16

Glucose-1-phosphate

Question 17

How is glucose-1-phosphate converted into glucose-6-phosphate

Answer 17

with the enzyme Phosphoglucomutase

Question 18

Why is glucose trapped in muscle?

Answer 18

muscle lacks the enzyme to release glucose

Question 19

What happens to glucose-6-phosphate in the liver?

Answer 19

endoplasmic reticulum (idk??)
It’s converted to free glucose
Glucose is sent to cytosol

Question 20

What turns glucose-6-phosphate into free glucose?

Answer 20

glucose-6-phosphatase

Question 21

When glucose-6-phosphate is sent to the cytosol in the liver what is done to the glucose?

Answer 21

glucose-6-phosphate is released into the blood stream

Question 22

What happens to glucose-6-phosphate when send to the muscle?

Answer 22

glucose-6-phosphate goes through glycolysis

Question 23

when is phosphorylase no longer effective at breaking down glycogen?

Answer 23

when there are four glucose molecules left prior to a branch point

Question 24

What two enzymes are required to breakdown a branch point in glycogen?

Answer 24

glucosyl-(4:4)-transferase

Amylo-alpha-(1,6)-glycosidase

Question 25

What does glucosyl-(4:4)-transferase do?

Answer 25

Removes the outer three glucose molecules prior to a branch point in glycogen

Question 26

What does Amylo-alpha-(1,6)-glycosidase do?

Answer 26

Removes the last glucose molecules prior to branch chain in glycogen

Question 27

What is the main enzyme in glycogenolysis regulation?

Answer 27

glycogen phosphorylase

Question 28

what stimulates glycogenolysis?

Answer 28

Liver (Fasting stimulates) | Muscle (stimulated during exercise)

Question 29

What are the hormonal regulation of glycogenolysis?

Answer 29

Glucagon (in liver) | Epinephrine (in liver/muscle)

Question 30

activation of adenylyl cyclase happens in response to what in glycogenolysis?

Answer 30

cAMP Protein kinase A (PKA) (ASK?)

Question 31

To what other hormone does Catecholamines work similar to?

Answer 31

Glucagon

Question 32

What regulates glycogen regulation?

Answer 32

``` Low blood glucose Epinephrine Calcium ADP, AMP Low energy charge ```

Question 33

Why is calcium released in muscle for glycogen degradation?

Answer 33

neural stimulation - releases Ca2+ from sarcoplasmic reticulum

Question 34

Why is Calcium released in liver?

Answer 34

epinephrine (unsure on how to phrase q)

Question 35

When Calcium binds to calmodulin (CaM) what happens?

Answer 35

It forms the CA2+-CaM complex and activates phosphorylase kinase

Question 36

Ca2+ and stress (don't know how to phrase)

Answer 36

Liver Epinephrine release from adrenal medulla (need glucose) Releases Ca2+ from ER to cytoplasm (binds to CaM) Ca2+-CaM activates phosphorylase kinase

Question 37

What happens when AMP binds to glycogen phosphorylase "b"?

Answer 37

no phosphorylation will occur

Question 38

What are the Enzymes used in glycogen breakdown?

Answer 38

``` Glycogen phosphorylase Phosphoglucomutase Glucosyl-(4:4)-transferase Amylo-alpha-(1,6)-glucosidase Glucose-6-phosphatase ```