These lines are from Lippincott Regarding ETC Inhibition of electron transport by respiratory inhibitors such as CO results in an inability to maintain the proton (H) gradient. Therefore, phosphorylation of ADP to ATP is inhibited, as are ancillary reactions such as calcium uptake by mitochondria, because they also require the H gradient. Q. I am not able to get what it says regarding calcium uptake by mitochondria Can anyone help