TBL 8

Question 1

Glycolysis irreversible steps

Answer 1

hexokinase and glucokinase (liver)
PFK-1 and PFK-2 (glycolysis)
pyruvate kinase,
lactate dehydrogenase (fermentation)

Question 2

Regulators of Glycolysis: Activators

Answer 2

ADP: sign of low energy
AMP: Stress signal
Calcium: signaling and insulin connection
F-1,6-bisphosphate and F-2,6-bisphosphate: allosteric

Question 3

Regulation of Glycolysis: inhibitors

Answer 3

ATP: sign of high energy
Citrate: downstream product ie road block
Glucose-6-Phosphate: road block

Question 4

Lactogen

Answer 4

mimics growth hormone
GH opposes insulin action and increases blood glucose. Glucokinase activity reduced. Mechanism of gestational diabetes

Question 5

Rate Limiting Enzyme of Glycolysis

Answer 5

PFK-1
Activated by: AMP and F-2,6-BP
Inhibited by: ATP and Citrate
produces: Fructose-1,6-Bisphosphate

Question 6

Fructose-2,6-Bisphosphate (Fed State)

Answer 6

Insulin, PFK2 ON, F-2,6-BP made, activating PFK-1. Drives glucose to pyruvate

Question 7

Fructose-2,6-Bisphosphate (Fasting State)

Answer 7

Glucagon activates Protein Kinase A. Phosphorylation of PKA activates FBPase-1. Glucose synthesis in the liver

Question 8

Pyruvate Kinase Deficiency

Answer 8

causes hemolytic anemia
low ATP, loss of ion balance osmotic fragility, swelling and lysis
echinocytes
increased 2,3-BPG alters Hgb binding

Question 9

Lactic Acidosis

Answer 9

excess lactate released by cells during glycolysis
Causes: poor oxygen support, LDH dysfunction or other metabolic conditions

Question 10

NADPH uses

Answer 10

Anabolic reactions: FA synthesis, adrenal cortex steroid hormone, mammary gland
Glutathione reduction: RBC erythrocytes
Drug Detox: liver CYP system
Immune Cells: oxidizes pathogens

Question 11

PPP oxidative (irreversible) phase

Answer 11

G6PD
6-phosphogluconate dehydrogenase

Question 12

PPP non-oxidative
reversible phase

Answer 12

Transketolase
Transaldolase
outcomes: purine and pyrimidine synthesis
F-6-P back to glycolysis
G-3-P to lipids
other rings to make other sugar products

Question 13

Transketolase

Answer 13

transfers 2 carbons
requires TPP (vitamin B1)

Question 14

Transaldolase

Answer 14

transfers 3 carbons

Question 15

Glucose 6-Phosphate Dehydrogenase Deficiency

Answer 15

X-linked recessive genetic defect (mostly men)
-prevalent in African descent, Middle Eastern,
- present hemolytic anemia (demand for NADPH is elevated)

Question 16

Demand for NADPH goes up from:

Answer 16

-infection
-fava beans
-oxidizing medications
(antibiotics, antimalarials)

Question 17

Oxidizing medications

Answer 17

Antibiotics
Antimalarials
Antipyretics
Sulfonamides

Question 18

Gluconeogenesis Regulators

Answer 18

Favored by glucagon

Question 19

Vitamin B1 Deficiency At Risk Groups

Answer 19

-alcoholics
-Starvation (eating disorder)
-pregnancy
-dialysis
-vomiting
-chronic diarrhea
- GI surgery

Question 19

Beriberi

Answer 19

Wet: vascular (edema)
Dry: neurological
-Reversible

Question 20

Wernicke-Korsakoff Syndrome

Answer 20

Wernicke (reversible): encephalopathy (nystagmus or opthalmoplegia, confusion, Ataxia)
Korsakoff (irreversible): memory loss, psychosis, permanent brain damage