Kerry Loombs - Lecture 2, 3

Question 1

Insulin is produced by

Answer 1

Islet beta cells in the pancreas

Question 2

Insulin is secreted in response to high or low blood glucose levels

Answer 2

High blood glucose levels

Question 3

What does Insulin do

Answer 3

Glucose from the circulation is converted into glycogen in the liver and muscle

Question 4

Glucagon is produced by

Answer 4

Islet alpha cells of the pancreas

Question 5

Glucagon is secreted in response to high or low blood glucose levels

Answer 5

Low blood glucose levels

Question 6

What does Glucagon do?

Answer 6

Glycogen break down in the LIVER to produce glucose that enters the circulation
(It does NOT act on muscle as there are no receptors present)

Question 7

Does Glucogon act on the liver, muscle or both

Answer 7

Liver only, no receptors in the musce

Question 8

Adrenaline (Epinephrine) is produced by

Answer 8

the Adrenal Glands

Question 9

Skeletal Muscle produces energy through

Answer 9

Glycolysis

Question 10

Skeletal muscle breaks down or produces glucose

Answer 10

Skeletal muscle breaks down Glucose

Question 11

Does the Liver breaks down or produces glucose

Answer 11

The liver produce glucose

Question 12

How does the Liver produce Glucose?

Answer 12

Through glycogenolysis or gluconeogenesis

Question 13

What does the enzyme Phosphofructokinase do?

Answer 13

• Convert Fructose-6-phosphate to Fructose-1,6-bisphosphate (fructose-1,6-P2)
• This is 1 of the irreversible steps in Glycolysis

Question 14

What does Pyruvate kinase do?

Answer 14

• Convert Phosphoenolpyruvate (PEP) into Pyruvate

- An irreversable step in Glycolysis

Question 15

Pyruvate Kinase is present as Type L and Type M, what does this mean

Answer 15

Type L predominates in the LIver

Type M predominates in muscle and the Brain

Question 16

What are the 3 domains in the Bifunctional enzyme?

Answer 16

Regulatory domain, Kinase domain and phosphatase domain

Question 17

Two of the 3 domains in the bifunctional polypeptide chain produce enzymes what are they?

Answer 17

• Kinase domain produces Phosphofrutokinase-2 (PFK2) which catalyses the formation of Fructose-2,6-bisphosphate
• Phosphatase domain produces fructose-2,6-bisphosphatase which catalyses the reformation of fructose-6-phosphate

Question 18

Of the 2 products produced by the bifunctional enzyme what one stimulates Glycolysis

Answer 18

Fructose-2,6 bisphosphate

Question 19

Can Epinephrine can act on both the liver and skeletal muscle,

Answer 19

Yes

Question 20

____ can release glucose into the blood stream. _____ cant release glucose into the blood stream because it lacks glucose-6-phosphatase

Answer 20

The Liver can release glucose into the blood stream. Skeletal muscle cant release glucose into the blood stream because it lacks glucose-6-phosphatase