Metabolism and its Control 1 Flashcards
What is ATP made of
- ribose
- adenine
- triphosphate
What are the two main glucose types
Haworth Projection
Fischer Projection
What is the overall yield of glycolysis
2X Pyruvate
2 ATP
2 NADH
Where does glycolysis take place
In the cytosol
What are the main stages of glycolysis
1) glucose is primed with two phosphorylation steps
2) one isomseration to form F-1,6-bp
3) this molecule splits to give GA-3-P
4) This molecules Is converted to pyruvate
3 steps in glycolysis
Priming stage
Splitting stage
Oxidoreduction- phosphorylation stage
What happens to pyruvate after glycolysis
It enters the TCA cycle
Or enter anaerobic respiration
What is gluconeogenesis
The reverse of glycolysis
What substances is Acetly CoA formed from
- amino acid
- Pyruvate
- fatty acid (reversible process)
What is the role of the PHD complex
PHD complex ( pyruvate dehydrogenase) removes carbon dioxide and a H+ ion to from NADH and acetyl CoA which binds to coenzyme A. This takes place in the matrix of the mitochondria
What is the cori cycle
When lactate is produced, the liver uses lactate to make glucose by gluconeogenesis for the glycolysis stage
What are the irreversible enzymes in glycolysis
Hexokinase
Phosphofructokinase
Pyruvate kinase
How does fatty acid contribute to metabolism
Fatty acids can be converted into acetyl CoA by beta oxidation
What are the irreversible enzymes in gluconeogenesis
Pyruvate carboxylase
Fructose 1,6 bisphosphatase
Glucose 6-phosphatase
What complications may occur in the glycolysis stage
Arsenic poisoning- this means that ATP generation is skipped
Describe the details of the glycolysis stage
Priming stage- energy investment
Glucose > glucose 6 phosphate > fructose 6 phosphate> fructose 1,6 bisphosphate.
Splitting stage- remember that fructose 1,6 bisphosphate splits into two products
Fructose 1,6 bisphosphate > dihydroxyacetone (DHAP) + glyceraldehyde-3-phosphate (GAP). GAP is the molecule we want.
DHAP is converted to GAP by triosphosphate isomerise
Oxidoreduction-phosphorylation stage- energy generation
GAP> 1,3-Bisphoglycerate> 3 phosphoglycerate> 2 phosphoglycerate> phosphoenolpyruvate> pyruvate.
How is the PHD complex regulated
The PHD complex is activated by phosphatase enzyme when it removes a phosphate group
The PHD complex is inactivated when kinase enzyme add a phosphate group to it
How is the kinase enzyme that inactivates the PHD complex regulated?
- Pyruvate blocks kinase activity so PHD complex is not inactivated
- Acetyl CoA activates the kinase enzyme to inactivate the PHD complex
Which two steps in glycolysis create ATP
- Conversion of 1,3 bisphospholycerate to 3, phosphoglcerate
- phosphoenolpyruvate to pyruvate
Which two steps in glycolysis use ATP
- glucose to glucose-6 phosphate
- fructose 6 phosphate to fructose 1,6 bisphosphate
What are the products of anaerobic respiration
Lactate only
Where does beta oxidation of fatty acids to make Pyruvate occur
In the mitochondrial matrix
Is the link reaction of marketing acetly CoA with Pyruvate dehydrogenase reversible or irreversible
Irreversible
