Carbs

Question 1

What is a disaccharide?

Answer 1

two monosachirides linked by an alpha glycosidic bond

Question 2

What is the normal plasma glucose level of a human?

Answer 2

4-5 mm, ruminant is around 3-4 mm

Question 3

What are the hypoglycemia and the hyperglycemia levels ?

Answer 3

hypo = half normal levels 
hyper = extended elevation above 10 mm

Question 4

What are the inhibitors of PFK1?

Answer 4

ATP, Citrate, H+

Question 5

What are the stimulators of PFK1?

Answer 5

Fructose 2,6- bisphosphate, AMP

Question 6

What are the inhibitors of pyruvate kinase?

Answer 6

ATP and alanine (allosteric), glucagon (covalent)

Question 7

What are the stimulators of pyruvate kinase?

Answer 7

allosteric- fructose-1,6-bisphosphate

Question 8

What are the inhibitors of pyruvate dehydrogenase?

Answer 8

NADH + acetyl CoA + ATP

Question 9

What are the stimulators of pyruvate dehydrogenase?

Answer 9

Mg+, Ca+, Insulin

Question 10

What is the function of the respiratory chain?

Answer 10

series of catalysts that collects and transports reducing equivalents (NADH and FADH2) directing them to final reaction with O2 to produce water
- catalysts are located on the inner mitochondrial membrane

Question 11

What is the yield of NADH via the respiratory chain?

Answer 11

2.5 ATP

Question 12

What is the yield of FADH2 via the respiratory chain?

Answer 12

1.5 ATP

Question 13

What is the total ATP generated from the TCA cycle?

Answer 13

10 ATP

Question 14

Name the two different types of shuttles, which one is more efficient?

Answer 14

Malate/asparate
glycerophosphate

malate/aspartate is more efficient (uses NADH rather than FADH2, which only generates 1.5 ATP)

Question 15

What is the name of the inhibitor of glucose- 6 phosphatase?

Answer 15

NADPH

Question 16

Name the four enzymes of the gluconeogenic quartet and state their function:

Answer 16

pyruvate carboxylase- in the mitochondria
phosphenolpyruvate carboxykinase- mitochondria and in the cytosol
fructose-1,6-bisphosphatase- cytosol
glucose-6-phosphatase- smooth ER

Question 17

Where does propionate come from?

Answer 17

comes from carbohydrate digestion within ruminants

Question 18

What is the stimulator for pyruvate carboxylase?

Answer 18

acetyl CoA is the stimulator

Question 19

What is the stimulator for phosphoenolpyruvate carboxykinase?

Answer 19

induced by glucocorticoids

Question 20

What is the stimulator for fructose-1,6-bisphosphatase?

Answer 20

F-2-6-bisphosphatase

Question 21

Where are glucagon receptors located?

Answer 21

liver and adipose tissue cells but not muscle cells

Question 22

Where is gluconeogenesis located?

Answer 22

liver (and in the kidney to a lesser extent)

Question 23

What is the effect on glycogon on fructose-2,6-bisphosphatas and pyruvate kinase?

Answer 23

inhibits pyruvate kinase

stimulates F-2,6-bisph

Question 24

What is the structure of glycogen?

Answer 24

polysaccharide of a-D-glucose linked a1-4 and branches a1-6

Question 25

Where is glycogen stored?

Answer 25

liver- 6%, muscle 1-2%

Question 26

What is the name of the enzyme that is involved in glucose synthesis?

Answer 26

glycogen synthase

Question 27

What is the name of the enzyme that is involved in the breakdown of glucose?

Answer 27

glycogen phosphorylase

Question 28

How much fuel is generated by the breakdown of glycogen

Answer 28

3 ATP

Question 29

What is the net effect of glucagon and adrenalin?

Answer 29

Net glycogen breakdown

Question 30

What is the effect of muscle contraction?

Answer 30

Net glycogen breakdown

Question 31

What is the net effect of insulin?

Answer 31

Insulin causes net glycogen synthesis