Glycolysis and Gluconeogenesis- Bikman

Question 1

When is insulin high?

Answer 1

After a meal, anticipating a meal, waking up

Question 2

What does insulin do?

Answer 2

Decreases glucose, ketones, and fat in the bloodstream

Question 3

What does glucagon do?

Answer 3

Increases glucose, ketonse, and fat in the bloodstream

Question 4

What type of cell does not have glucagon receptors?

Answer 4

Myocytes - aka muscle cells

Question 5

Which enzymes are irreversible in glycolysis?

Answer 5

Hexokinase or Glucokinase
PFK-1
Pyruvate Kinase

Question 6

Which enzymes in glycolysis use ATP?

Answer 6

Hexokinase or Glucokinase

PFK-1

Question 7

Which enzymes in glycolysis create NADH?

Answer 7

Glyceraldehyde 3 Phosphate Dehydrogenase

Question 8

Which enzymes in glycolysis create ATP

Answer 8

Phosphoglycerate Kinase

Pyruvate Kinase

Question 9

Which enzyme converts pyruvate to acetyl-CoA? what does it require to do so? And what are its products?

Answer 9

Pyruvate Dehydrogenase
It needs NAD and CoA-SH
Its products are acetyl-CoA, NADH, and CO2

Question 10

What inhibits Pyruvate Dehydrogenase?

Answer 10

Acetyl-CoA, NADH, and ATP

Phosphorylation by PDK (pyruvate dehydrogenase kinase) also inhibits

Question 11

If ATP is high and AMP is low, what happens to glycolysis?

Answer 11

It inhibits glycolysis

Question 12

If ATP is low and AMP is high, what happens to glycolysis?

Answer 12

It activates glycolysis

Question 13

What is the effect of high fructose 2,6 bisphosphatate?

Answer 13

It activates PFK-1

Question 14

What happens if pyruvate kinase (PK) is phosphorylated?

Answer 14

It is inhibited

Question 15

What are the effects of insulin in glycolysis?

Answer 15

It activates PK, PFK-1, and glucokinase

Question 16

What are the effects of glucagon in glycolysis?

Answer 16

It deactivates PK, PFK-1, and glucokinase

Question 17

What is the bypass reaction for glucokinase?

Answer 17

G6P is converted by to glucose with glucose-6-phosphotase

Question 18

What is the parallel enzyme with PFK-1 and what is the product?

Answer 18

PFK-2 turns G6P to fructose -2,6-bisphosphate

Question 19

What is the bypass reaction for PFK-1?

Answer 19

F1,6BP and F2,6BP is turned back to F6P by fructose 1,6 bisphosphatase

Question 20

What is the bypass reaction for pyruvate kinase?

Answer 20

pyruvate is converted to OAA by pyruvate carboxylase. OAA is then turned back to PEP by PEPCK

Question 21

What are some derivatives of pyruvate?

Answer 21

lactate, alanine, cystine, glycine, serine, tryptophan

Question 22

How does pyruvate become lactate?

Answer 22

lactate dehydrogenase uses up two NADHs. NAD is recycled back into glycolysis

Question 23

What occurs in the Cori cycle?

Answer 23

pyruvate is converted to lactate by lactate dehydrogenase. The lactate can either go to the muscles or the heart to be converted back to pyruvate.

Question 24

Why can we not get glucose from a fatty acid?

Answer 24

you get a net zero of carbons

Question 25

What can glycerol become?

Answer 25

A splitting derivative (DHAP or PGAL). It requires 2 ATP and 2NADH

Question 26

When does anerobic glycolysis occur?

Answer 26

In RBC’s that lack mitochondria
In muscles that are worked vigorously
In tumors
In ischemia (blood blockage)