Biochem Pathway

Question 1

Glycolysis

Answer 1

Phosphofructokinase,

UP: F2,6BP & AMP
Down: Citrate and ATP

Question 2

Gluconeognesis

Answer 2

Fructose-2,6-bisphosphatase

UP: AMP & acetyl-CoA

Down: F2,6BP & AMP

Question 3

TCA

Answer 3

Isocitrate dehydroagenase

Up: ADP

Down: NADH, ATP

Question 4

Glycogenesis

Answer 4

Glycogen synthase;

Up: phosphatase
G6P, insulin, cortisol

Down: PKA mediated glycogen phosphoylase kinase;
Epinephrine, glucagon

Question 5

Glycogenolysis

Answer 5

Glycogen phosphorylase

Up: glucagon, epinephrine, AMP
Down: G6P, insulin, ATP;

Question 6

HMP Shunt

Answer 6

G6PD

UP: NADP
Down: NADPH

Question 7

De novo pyrimidine synthesis

Answer 7

Caramoyl phophaste synthase II

Question 8

De novo purine synthesis

Answer 8

Glutamine- phophoribosylpyrophosphate (PRPP) amidotransferase

Down: AMP, GMP, IMP

Question 9

Urea cycle

Answer 9

Carbamoyl phosphate synthase I

Up: N-acetylglutamate

Question 10

Fatty Acid synthesis

Answer 10

Acetyl-CoA carboxylase (ACC)

up: insulin, citrate
down: glucagon, palmotyl-CoA

Question 11

Fatty acid oxidation

Answer 11

Carnitine transferase I

down: Malonyl-CoA (production of Acetyl-CoA Carboxylase)

Question 12

Ketogensis

Answer 12

HMG-CoA Synthase

Question 13

Cholesterol Synthesis

Answer 13

HMC-CaA redutase

Up: insuline, thyroxine
Down: Glucagon, Cholesterol

Question 14

Fastest monosaccaride into cycle

Answer 14

Fructose, goes to F1P –> DHAP & gluceraldehyde by aldosase B

Question 15

Glucokinase

Answer 15

Beta-islets & liver

high Km & Vmax;

down by F6P;

Question 16

Hexokinase

Answer 16

all tissue but liver and beta-islets

low Km & Vmax;
down by G6P;

Question 17

Phosphoenol pyruvate

Answer 17

up: F1,6BP;
down: ATP, alanine

Question 18

Pyruvate dehydrognease

Answer 18

Cofactors: B1, B2, B3, B5, Lipoic acid (inhibited by arsenic)

up: NAD+/NADH ratio, ADP, Ca++
down: Acetyl-CoA; NADH, ATP

Deficiency caused build up of lactate (via LDH) & alanine (via ALT/cytosol)

Question 19

Arsenic

Answer 19

incorporated into 1,3-BPG (not AtP by glycolysis)

Inhibits Lipoic acid (no pyruvate dehydrogenase, alpha-ketogluterate dehydrogenase);

Present: garlic breath, rice-water stools, vomiting;

Question 20

Pyruvate dehydrognease deficiency

Answer 20

Deficiency caused build up of lactate (via LDH) & alanine (via ALT/cytosol)

Present: neurological defects, lactic acidosis, high alanine content

Treat with lysine and leucine; only eat ketogenic;

Question 21

Reversible TCA Enzymes

Answer 21

Citrate synthase, Isocitrate dehydrogenase, Alpha-ketogluterate dehydrogenase

Question 22

Alpha-ketogluterate dehydrogenase

Answer 22

down: NADH, ATP, Succinyl-CoA

Question 23

Tryptophan products

Answer 23

B6: NIacin

B6/BH4: Serotonin & melatonin

Question 24

Histidine

Answer 24

B6: Histamine

Question 25

Glycine

Answer 25

B6: porphyrin & heme

Question 26

Glutamine

Answer 26

B6: GABA None: Glutathione

Question 27

Arginine

Answer 27

None: Creatine & Urea BH4: NO;