Biosynthesis of Glycogen and Glucose-6-Phosphate

Question 1

Glycogen is produced when

Answer 1

When the levels of glucose in the blood are sufficient.

• Allows glucose to be stored for later use
• Occurs mainly in the liver and skeletal muscle

Question 2

How is glucose converted to glycogen

Answer 2

Glucose is first converted to glucose-6-phosphate and then converted to glycogen.

Question 3

How is glycogen converted to glucose

Answer 3

Glycogen is converted to glucose-6-phosphate (intermediary) when we have low levels of glucose in our blood. And then that can be converted to glucose.

Question 4

Glucose-6-phosphate is an intermediate in

Answer 4

• Glycolysis
• Gluconeogenesis
• Glycogen synthesis
• Glycogen breakdown (glycogenolysis)
• Pentose phosphate pathway

Question 5

Another name for the pentose phosphate pathway

Answer 5

Hexose Monophosphate Shunt

Question 6

What does the pentose phosphate pathway convert glucose-6-phosphate into?

Answer 6

Converts glucose-6-phosphate into NADPH and pentoses (5 carbon sugars)

Question 7

NADPH

• What is its role?
• What is its oxidized form?
• Used as a source of what?
• 60% of it is produced during what pathway and at what stage?

Answer 7

• An electron carrier that can accept 2 electrons and 1 proton.
• Oxidized form is NADP+
• Used as a source of electrons in biosynthesis (reactions that make stuff like fatty acids or cholesterol)
• 60% of NADPH is produced during the pentose-phosphate pathway
• Produced during the oxidative stage

Question 8

Where does the pentose phosphate pathway occur

Answer 8

In the cytosol

Question 9

Pentoses

• What are they
• Used for what?
• Produced during which stage

Answer 9

• 5 carbon sugar (mainly ribose 5 phosphate)
• used as building blocks for nucleotides
• produced during the non-oxidative stage

Question 10

2 phases during pentose phosphate pathway

Answer 10

1. Oxidative phase- produces NADPH

2. Non-oxidative phase- Pentose is made