GLUCONEOGENESIS (4th question group) Flashcards
what is gluconeogenesis (GNG) ?
biosynthesis of glucose from no carbohydrate sources
in which species does GNG take place continuously and why?
Ru
they have a low blood sugar conc, especially during the lactation period
name glucose dependant tissues
brain (nerve cell)
erythrocytes (no mitochondria so no ATP production)
adrenal medulla
testis
why can an interruption of glucose to the brain be fatal?
as it has no glycagon reserve and glucose is its primary fuel
where does GNG take place?
liver
kidney (cytoplasm)
what enzymes regulate GNG?
fructose - 1, 6 - phophotase
pyruvate carboxylase
how does insulin effect GNG?
decreases GNG, blood sugar, cAMP levels
increases glycolysis
how does glucagon effect GNG?
increases GNG, blood sugar, cAMP levels
decreases glycolysis
The enzyme which catalyzes the conversion of pyruvate to oxaloacetate?
Pyruvate carboxylase
which coenzyme is required to convert pyruvate to oxaloacetate?
biotin
Oxaloacetate is reduced to malate by?
Malate dehydrogenase
Gluconeogenesis involves conversion of?
Pyruvate to glucose
Formation of one molecule of glucose from pyruvate requires?
4 ATP, 2 GTP and 2 NADH
The main source of glucose carbons for gluconeogenesis is?
Alanine
