Carbohydrates 4 Flashcards
Gluconeogenesis
Need to bypass the 3 irreversible reactions of glycolysis
How many reactions used to bypass the irreversible reactions?
4 - step 10 needs 2 steps to bypass
pyruvate->oxaloacetate->PEP
Reactions A+B
Mitochondria - bypass 10
Reactions C+D
Cytosol
What tissues use glucose?
Brain, CNS, RBC and testes
What do the bypass reactions do?
- Prevent gluconeogenesis and glycolysis cancelling eachother out
- Allows independent control
Step 10
Pyruvate->oxaloacetate->PEP produce ATP
Starting with pyruvate or lactate is malate made?
Pyruvate
Reaction C
F-1,6-BP ==> F-6-P
Reaction D
G-6-P ==> Glucose
Where does reaction D only occur?
ER ==> usually not transferred back to free glucose
Where of the 3 sugars enter?
Galactose = G6P Fructose= F-1,6-P or DHAP
Where is most fructose metabolised?
Liver
What does the pentose phosphate pathway do?
Produces NADPH -> liver, adrenal cortex,
Produces Pentoses,
Metabolise pentose in diet
Name the 2 steps of pentose phosphate pathway
Oxidative - reversible
non oxidative - irreversible
