Studies of respiration in the mitochondria of isolated skeletal muscle have shown that the process cannot usually proceed in the absence of ADP or inorganic phosphate (the substrates required for ATP synthesis) from the medium in which the mitochondria are incubated. In patient X initial studies of isolated mitochondria showed that respiration could proceed at nearly maximal rate in the absence of ADP. When ADP was supplied in excess, phosphorylation to produce ATP proceeded as normal.
From these first studies which biochemical pathway is likely to be dysfunctional in patient X.
M (Specialist biology tutor)