Carb Metabolism

Question 1

Sucrose

Answer 1

Glucose-Fructose

Question 2

Lactose

Answer 2

Galactose-Glucose

Question 3

Galactose

Answer 3

Glucose-Glucose

Question 4

Monosaccharides

Answer 4

Glucose, galactose, fructose, mannose

Question 5

Glut 1 location

Answer 5

Blood- brain, testes, placenta, retina
(HIGH AFFINITY FOR GLUCOSE)

Question 6

Glut 2 location

Answer 6

Liver, kidney, pancreatic beta cells, serosa intestinal mucosal cells

Question 7

Glut 3 location

Answer 7

Brain (neurons)

Question 8

Glut 4 location

Answer 8

Adipose, skeletal muscle, heart muscle
(INSULIN SENSITIVE TRANSPORTER)!

Question 9

Glut 5 location

Answer 9

Intestinal epithelium, spermatozoa

Question 10

Breaks glycogen down into glucose-1-phosphate

Answer 10

Glycogen phosphorylase

Question 11

Converts glucose to glucose-6-phosphate

Answer 11

Hexokinase/ glucokinase (liver)

Question 12

Commits glucose-6-phosphate to glycogen formation

Answer 12

Phosphoglucomutase

Question 13

Branching enzyme, adds glycogen primer to form, glycogen from UDP-G, RATE LIMITING ENZYME FOR FORMATION OF GLYCOGEN!

Answer 13

Glycogen synthase

Question 14

Causes glycogen upregulation

Answer 14

Insulin

Question 15

Causes glucose upregulation

Answer 15

Epinephrine, glucagon (liver), GTP (high energy availability)

Question 16

Location of glucose breakdown

Answer 16

Cytosol

Question 17

Glycolysis rate limiting step 1

Answer 17

Step 1- conversion of glucose to G-6-P by hexokinase (skeletal muscle) or glucokinase (liver)

Question 18

Glycolysis rate limiting step 2

Answer 18

Fructose-6-phosphate to fructose 1,6-bisohosphate by PHOSPHOFRUCTOKINASE

Question 19

Glycolysis rate limiting step 3

Answer 19

Glyceraldehyde-3-phosphate to 1,3-biphosphoglycerate by GLYCERALDEHYDE-3-PHOSPHATE DEHYDROGENASE

Question 20

Glycolysis rate limiting step 4

Answer 20

Conversion of Phosphoenol-pyruvate to pyruvate by PYRUVATE KINASE

Question 21

Location of pyruvate oxidation

Answer 21

Mitochondrial matrix

Question 22

Pyruvate oxidation cofactors

Answer 22

B1 (thiamin), B2 (riboflavin), B3 (niacin), lipoid acid, coenzyme A

Question 23

Location of pyruvate in anaerobic conditions

Answer 23

Cytosol, esp RBCs but also skeletal muscle

Question 24

Purpose of pyruvate in anaerobic glycolysis

Answer 24

Regenerate NAD+

Question 25

Glycolysis

Answer 25

Substrate: glucose Location: cytosol Product: pyruvate Key intermediates: glucose-6-phosphate Key enzyme step: PFK-1 (hexokinase and glucokinase) Energy products: 2 pyruvate, 2 ATP, 2 NADH

Question 26

Pyruvate oxidation

Answer 26

Substrate: pyruvate Location: mitochondrial matrix Product: acetyl coA Key intermediates: Key enzyme step: pyruvate dehydrogenase (NAD, niacin, FAD, TPP, CoA, lipoid acid) Energy products: 2 acetyl coA, 2 NADH

Question 27

Anaerobic Glycolysis

Answer 27

Substrate: pyruvate Location: cytosol Product: lactate Key enzyme step: lactate dehydrogenase Energy products: -1 NADH

Question 28

Krebs Cycle

Answer 28

Substrate: acetyl coA Location: mitochondrial matrix Product: CO2, NADH, FADH2, GTP Key intermediates: many Key enzyme step: isocitrate dehydrogenase, alpha ketoglutarate dehydrogenase Energy products: 1 FADH2, 3 NADH

Question 29

Glycogen Synthesis

Answer 29

Substrate: glucose Location: cytosol Product: glycogen Key intermediates: UDP-glucose Key enzyme step: phosphoglucomutase Energy products: -1 ATP and glucose

Question 30

Penrose Pathway (HMP Shunt)

Answer 30

Substrate: glucose-6-phosphate Location: cytosol Product: NADPH, ribose sugars Key intermediates: NADPH Key enzyme step: glucose-6-phosphate dehydrogenase Energy products:

Question 31

Ketogenesis

Answer 31

Substrate: acetyl coA Location: mitochondrial matrix Product: beta hydroxybuterate dehydrogenase, acetone, acetoacetate Key intermediates: HMG coA Key enzyme step: HMG CoA synthetase Energy products: -2 acetyl coA, -1 NADH

Question 32

Ketone Degredation

Answer 32

Substrate: beta hydroxybuterate, acetone, acetoacetate Location: mitochondrial matrix Product: acetyl coA Key intermediates: HMG CoA Key enzyme step: beta hydroxybuterate dehydrogenase Energy products: 2 acetyl coA, 1 NADH, -1 GTP