Glycolysis And Gluconeogenesis

Question 1

What do SGLTs do?

Answer 1

Glucose uptake from digestive tract

Glucose recovery from the kidneys

Question 2

What do GLUTs do?

Answer 2

Move glucose down its concentration gradient

Question 3

Where is GLUT 4 found?

Answer 3

Skeletal muscle, cardiac muscle, adipocytes

Question 4

Is GLUT 4 regulated by insulin?

Answer 4

Yes.

Question 5

What happens when insulin binds to its receptor?

Answer 5

Triggers cascade that will activate AS160 to tell GLUT4 to release to membrane and start taking in glucose.

Question 6

How does GLUT 4 become activated in muscle cells?

Answer 6

Muscle contraction

Question 7

When is insulin chronically high?

Answer 7

Insulin resistant (pre diabetes) or diabetes

Question 8

What does insulin do in liver, muscle, and adipose cells?

Answer 8

Liver - inhibit ketogenesis and activate lipogenesis and glycogen edits
Muscle - glucose uptake and anabolism
Adipose - glucose uptake, lipogenesis, and adipogenesis

Question 9

What counters insulin?

Answer 9

Glucagon, catecholamines, cortisol, growth hormones

Question 10

Insulin is the only hormone that

Answer 10

promotes fat storage and inhibits fat use

Question 11

What does glucagon do in liver, muscle, and adipose cells?

Answer 11

Liver - glycogenesis, gluconeogenesis, ketogenesis
Muscle - NOTHING
Adipose - lipolysis

Question 12

Glucokinase

Answer 12

Glycolysis step 1
Glucose to G6P
Irreversible

Question 13

Phosphohexase isomerism

Answer 13

Glycolysis step 2

G6P to F6P

Question 14

Phosphofructokinase-1

Answer 14

Glycolysis step 3
F6P to F1,6BP
Irreversible

Question 15

Aldolase

Answer 15

Glycolysis step 3
F1,6BP to DHAP and G3P
Splits in two 3 carbon chains
Prep stage is over

Question 16

Glyceraldehyde-3-phosphate dehydrogenase

Answer 16

Glycolysis step 5
G3P to 1,3BPG
Make NADH

Question 17

Phosphoglycerate kinase

Answer 17

Glycolysis step 6
1,3BPG to 3PG
Substrate level phosphorylation (make ATP)

Question 18

Phosphoglycerate mutate

Answer 18

Glycolysis step 7

3PG to 2 PG

Question 19

Enolase

Answer 19

Glycolysis step 8

2PG to PEP (high energy molecule)

Question 20

Pyruvate kinase

Answer 20

Final step glycolysis
PEP to pyruvate
Irreversible
Substrate level phosphorylation

Question 21

Pyruvate dehydrogenase reaction

Answer 21

Pyruvate enters the mito matrix via a pyruvate carrier and reacts with coenzyme a, NAD+, and the pyruvate dehydrogenase complex to make acetyl CoA

Question 22

3 enzymes in the PDH complex

Answer 22

TPP, lipomamide, FAD

Question 23

Regulation of the PDH reaction

Answer 23

ATP, NADH, acetyl CoA, phosphorylation of PDH kinase, dephosphorylation of PDH phosphotase

Question 24

High [ATP] and low [AMP] favors

Answer 24

Gluconeogenesis

Question 25

How does insulin regulate glycolysis which blood glucose levels are high?

Answer 25

Decrease F26BPase = Increase [F26BP] = Increase PFK1 activity
Decrease phosphorylated PK = increase PK activity

Favors glycolysis, not gluconeogenesis

Question 26

How does glucagon regulate glycolysis when blood glucose levels are low?

Answer 26

Increase [cAMP] = Increase PKA:
Decrease [F26BP] = Decrease PFK1
Increase phosphorylated PK = Decrease PK activity

Favors gluconeogenesis not glycolysis

Question 27

Glucose-6-phosphotase

Answer 27

Gluconeogenesis
G6P to glucose
Only in liver

Question 28

Fructose 1,6 bisphosphotase

Answer 28

Gluconeogenesis

F16BP to F6P

Question 29

How do you get from pyruvate to PEP?

Answer 29

Pyruvate is transferred through the IMM via a pyruvate transporter
Pyruvate to OAA via Pyruvate carboxylase
Oxaloacetate to malate via MDH
Malate transported outside of the matrix then turned back into oxaloacetate via ODH
Oxaloacetate to PEP via PEPCK

Question 30

SGLTs are present in

Answer 30

Intestine and kidney epithelial cells

Question 31

Regulation of F16BPase

Answer 31

PFK2 turns F6P to F26BP which inhibits F16BPase
F26BPase turns F16BP to F6P
Favors glycolysis