State the condition under which pyruvate would be metabolised by pathway 2.
Name compound X from the figure.
Name the two reaction types that occur in pathway 1.
Suggest a mammalian cell that is unable to carry out pathway 1. Give a reason for your answer.
ATP is synthesised during glycolysis. Name the process responsible for ATP synthesis.
Define the term respiratory quotient, giving it as a ratio.
Explain why a hummingbird that has gone without food for some time has an RQ value of $0.7$, whereas a hummingbird that has eaten has an RQ value of $1.0$.
Fig. 6.3 indicates that hummingbirds have a greater percentage of respiration using substrates obtained directly from the diet. Calculate how many times larger this figure is for hummingbirds than for humans. Show your working and give your answer to two decimal places.
Suggest the advantages to a hummingbird of obtaining most of its respiratory substrates from its diet while exercising.
Suggest the advantages for a hummingbird of taking most of its respiratory substrates from its diet while it is exercising.