Gluconeogenesis

Question 1

Gluconeogenesis

Answer 1

Glucose synthesis from pyruvate and other intermediates
Occurs in mitochondria and cytoplasm - generally in the liver under fasting conditions (sometimes kidneys); the glucose is generally then sent to the brain, muscle, and RBCs

Question 2

Non-carbohydrate precursors of pyruvate

Answer 2

Lactate
Amino acids (diet and breakdown of muscle proteins during starvations)
Glycerol - breakdown of fat

Question 3

Alcoholism and Gluconeogenesis

Answer 3

When NADH levels are high (happens with high alcohol consumption), pyruvate is converted to lactate, inhibiting gluconeogenesis.
Lack of glucose can lead to hypoglycemia and excess lactate to lactic acid buildup

Question 4

Oxaloacetate transport and phosphorylation

Answer 4

Oxaloacetate is converted to malate, transported to the cytoplasm from the mitochondria, and then reconverted by the oxaloacetate, where it can then be converted to PEP
-oxaloacetate –> pyruvate reaction is catalyzed by phosphoenolpyruvate carboxykinase (requires GTP)

Question 5

Glucose-6-phosphatase

Answer 5

catalyzes conversion of glucose-6-P to glucose, allowing the liver to transport glucose out of its cells and into cells that need glucose