Gluconeogenesis

Question 1

Macromolecules that can be synthesized into glucose

Answer 1

Amino acids (especially alanine)
Lactate
Pyruvate
Glycerol

Question 2

Net reaction of gluconeogenesis

Answer 2

2 pyruvate + 4 ATP + 2 GTP + 2 NADH + 2H+ + 6H2O -> glucose + 4 ADP + 2GDP + 2NAD+ + 6 phosphate
6 nucleotides: more energy is needed to make glucose than is generated from its consumption

Question 3

3 steps that are different from glycolysis

Answer 3

Pyruvate -> phosphoenolpyruvate
Fructose 1,6-bisphosphate -> fructose-6 phosphate
Glucose 6-phosphate -> glucose

Question 4

Pyruvate -> phosphoenolpyruvate

Answer 4

Pyruvate -> oxaloacetate (enzyme: pyruvate carboxylase; 2 ATP used)
Oxaloacetate -> phosphoenolpyruvate (enzyme: phosphoenolpyruvate carboxykinase; 2 GTP used)

Question 5

Fructose 1,6-bisphosphate -> fructose 6-phosphate

Answer 5

Enzyme used is fructose 1,6-bisphosphatase (rather than phosphofructokinase-1)

Question 6

Glucose 6-phosphate -> glucose

Answer 6

Enzyme used is glucose 6-phosphatase (rather than hexokinase)

Question 7

Cori cycle

Answer 7

Muscles generate lactic acid through anaerobic glycolysis that is recycled back to glucose in the liver

Question 8

Glycerol metabolism to glucose

Answer 8

2 steps:
Glycerol -> glycerol 3-phosphate (glycerol kinase)
Glycerol 3-phosphate -> dihydroxyacetone phosphate

Question 9

Difference in products in glycerol 3-phosphate -> dihydroxyacetone phosphate based on where reaction takes place

Answer 9

Cytosol: NADH is a product

Mitochondrial membrane: QH is a product