Answer: Electron transport chain is a final stage of aerobic cellular respiration that involves the formation of large amount of ATP ( adenosine triphosphate) that is the energy currency of the cell.
It takes place in the inner mitochondrial membrane. Electrons are passed through various protein complexes present in the inner mitochondrial membrane.
When this happens, protein complexes push protons from mitochondrial matrix to the inter-membrane space, creating a proton gradient outside. ATP synthase is a final protein complex that forms ATP using the concentration gradient of protons.
Because male chromosomes are XY, compared to females having two Xs (XX). If a female has an x-linked disorder to one of their Xs, the other X will be able to cover for that shortcoming. Males on the other hand do not have another X, thus, those disorders are expressed.