Krebs Cycle Flashcards
When does this take place?
After the link reaction
Where does this take place?
In the mitochondrial matrix
What does this reaction use?
Acetyl co-enzyme A from Link reaction
And NAD and FAD which are co enzymes in the matrix
What happens to the acetyl co enzyme A
Joins with a 4 carbon molecule to form a 6 carbon molecule
Releases the co-enzyme A
What happens to the 6 carbon compound?
Is oxidised back to the 4 carbon molecule that the acetyl coenzyme A at the start of the cycle
So 2 CO2 molecules are released as a result
And co enzymes NAD and FAD accept hydrogen lost so reduced to NADH and FADH
Oxidation of 6 carbon molecule also produces…
1 ATP molecule by substrate level phosphate
Where ADP gains a phosphate group attached to substrate (an intermediate)
How does the cycle restart?
4 carbon molecule is regenerated by oxidation of 6 carbon molecule
How many turns of the cycle per glucose?
2 turns
Because 1 glucose produces 2 pyruvate, 2 acetate, 2 acetyl co enzyme A = 2 turns
How is 6CO2 released as an overall waste product of respiration? Where is the 6 CO2 obtained from?
Per 1 glucose:
2 CO2 is gained from Link reaction where 2 pyruvate is oxidised to acetate, releasing 2 CO2 molecules
4 CO2 is gained from 2 turns of Krebs cycle
What is the point in the Krebs cycle?
To produce large amounts of NADH and FADH
Co enzymes
A non protein compound necessary for the function of an enzyme
BUT ARENT ENZYMES!!!
In respiration, they help another substance become oxidised by gaining the hydrogen lost from the substance to be reduced
Examples of Co enzymes
NAD and FAD
NADP from photosynthesis
