Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
25 Cards in this Set
- Front
- Back
|
Products of the Pentose Phosphate Shunt (PPS) |
2 NADPH ribose-5-p 2 F6P 2 G3P |
|
|
What is NADPH used for? |
Biosynthesis of fatty acids, cholesterol, neurotransmitters & nucleotides Acts as an anti-oxidant |
|
|
What products are from the oxidative stage? |
2 NADPH and Ribulose-5-phosphate |
|
|
What products are from the non oxidative stage? |
F6P and Glyceraldehyde 3 phosphate |
|
|
Transketolase |
Used in the non oxidative stage and transfers 2 carbons |
|
|
Transaldolase |
Used in the non oxidative phase and transfers 3 carbons |
|
|
What tissues use the PPS? |
Adrenal glands, Liver, Testes, Adipose, Mammary, RBC's |
|
|
Three enzymes of the Oxidative Stage |
1) Glucose 6 phosphate DHG (NADPH) 2) Gluconolactonase 3) 6-phosphogluconate DHG (NADPH) |
|
|
Glucose 6 DHG regulation |
Inhibited by NADPH Activated by GSSH |
|
|
Why is the oxidative phase so active in RBC's and hepatocytes? |
Detoxification and fatty acid synthesis in the liver and blood carries oxygen and oxygen is very reactive and can become free radicals |
|
|
Where is oxidative phase not present? |
Muscle cells |
|
|
The 4 enzymes of PPS |
1) Phosphopentose isomerase 2) Phophopentose wpimerase 3) Transketolase ( Requires TPP) 4) Transaldolase |
|
|
TPP |
Thiamine pyrophosphate - Vitamin B1 |
|
|
Why is fructose metabolized so fast? |
It skips all the regulatory points of glycolysis and is metabolized way too quickly. Skips Hexokinase and PFK1 |
|
|
Glycogenolysis |
Glucose can be rapidly delivered to the blood stream when needed upon degradation of glycogen |
|
|
Glycogenesis |
Enough glucose and energy triggers synthesis of gycogen |
|
|
Glycogenesis Pathway |
1) G6P to G1P 2) Synthesis of UDP - glucose 3) Glycogen synthase (alpha 1-4 linkages) 4) Branching enzyme (alpha 1-6 linkages every4 to 8 residues |
|
|
Why is there branching in glycogen? |
Branching accelerates the rate of glucose release during degradation due to increase nonreducing ends available |
|
|
Where is glycogen stored? |
Liver and Muscle |
|
|
Glycogenolysis stages |
1) Glycogen phosphorylase When there are only 4 glucose left the outer 3 will be removed and added to the linear chain 2) Debranching enzyme Removes the single glucose residue attached to each branch point |
|
|
Metabolic regulation of glycogen |
1) Glucagon 2) Insulin 3) Epinephrine |
|
|
Glucagon affect on glycogen synthase |
glycogenesis inhibition |
|
|
Glucagon affect on phosphorylase kinase |
Glycogenolysis stimulation |
|
|
Insulin affect on glycogen synthase |
Activation and glycogenesis |
|
|
Insulin affect on Phosphorylase kinase |
glycogenolysis inhibition |
