Glycolysis and fermentation
1.[1p] Glycolysis invests two ATP and produces four. What is the net yield of ATP per glucose?
Glycolysis invests two ATP and produces four. What is the net yield of ATP per glucose?
2.[2p] Why does the pathway spend two ATP before earning any?
Why does the pathway spend two ATP before earning any?
The answer is: Phosphorylation traps the sugar inside the cell, commits it to the pathway, and sets up a molecule that can be cleaved in half
The answer is: Phosphorylation traps the sugar inside the cell, commits it to the pathway, and sets up a molecule that can be cleaved in half
The answer is: Phosphorylation traps the sugar inside the cell, commits it to the pathway, and sets up a molecule that can be cleaved in half
3.[3p] In the glyceraldehyde 3-phosphate dehydrogenase step, where does the phosphate that ends up in ATP come from?
In the glyceraldehyde 3-phosphate dehydrogenase step, where does the phosphate that ends up in ATP come from?
The answer is: Free inorganic phosphate in solution, captured as an acyl phosphate using the energy of an oxidation
The answer is: Free inorganic phosphate in solution, captured as an acyl phosphate using the energy of an oxidation
The answer is: Free inorganic phosphate in solution, captured as an acyl phosphate using the energy of an oxidation
4.[2p] Two ATP at the standard 30.5 kJ/mol are captured from a glucose containing 2870 kJ/mol. What percentage of the available energy is that, to one decimal place?
Two ATP at the standard 30.5 kJ/mol are captured from a glucose containing 2870 kJ/mol. What percentage of the available energy is that, to one decimal place?
5.[1p] Fermentation to lactate or ethanol yields additional ATP beyond what glycolysis has already made.
Fermentation to lactate or ethanol yields additional ATP beyond what glycolysis has already made.
The answer is: False
6.[3p] What is fermentation actually for?
What is fermentation actually for?
The answer is: Reoxidising NADH so that NAD⁺ is available and glycolysis can keep running
The answer is: Reoxidising NADH so that NAD⁺ is available and glycolysis can keep running
The answer is: Reoxidising NADH so that NAD⁺ is available and glycolysis can keep running
7.[2p] Match each molecule to its role in glycolysis.
Match each molecule to its role in glycolysis.
Phosphofructokinase
1,3-bisphosphoglycerate
Phosphoenolpyruvate
Lactate dehydrogenase
a donor whose power comes from tautomerisation after transfer
an acyl phosphate that donates phosphate to ADP
regenerates NAD⁺ in muscle
the committed step and the main control point
Show the answer
Phosphofructokinase: the committed step and the main control point 1,3-bisphosphoglycerate: an acyl phosphate that donates phosphate to ADP Phosphoenolpyruvate: a donor whose power comes from tautomerisation after transfer Lactate dehydrogenase: regenerates NAD⁺ in muscle
8.[2p] Which regulators act on phosphofructokinase, and in the direction stated?
Which regulators act on phosphofructokinase, and in the direction stated?
Select all that apply
The answer is: ATP inhibits it, AMP activates it, Citrate inhibits it
9.[2p] Put these glycolytic species in the order they appear.
Put these glycolytic species in the order they appear.
Phosphoenolpyruvate
Glucose 6-phosphate
Fructose 1,6-bisphosphate
Glyceraldehyde 3-phosphate
Pyruvate
Show the answer
a, b, c, d, e