Date | May 2010 | Marks available | 1 | Reference code | 10M.3.SL.TZ1.11 |
Level | Standard level | Paper | Paper 3 | Time zone | Time zone 1 |
Command term | Label | Question number | 11 | Adapted from | N/A |
Question
The diagram below shows part of the respiratory pathway. The number of carbon atoms in each molecule is indicated.
Label pyruvate and acetyl coenzyme A on the diagram above.
Indicate two places where decarboxylation occurs on the diagram.
List one product other than carbon dioxide formed in this stage of respiration.
State precisely where in a cell this stage of respiration is occurring.
Markscheme
(i) and (ii)
(i) and (ii)
NADH + H+ /FADH2 /ATP (or GTP)
matrix of mitochondrion
Examiners report
The majority were able to gain three marks from the parts of this question.
The majority were able to gain three marks from the parts of this question.
The majority were able to gain three marks from the parts of this question.
As the question asked, candidates need to be precise in their answers, and many simply gave “mitochondria“ as their answer instead of specifying “matrix”.