Q. In chloroplast, the highest number of protons are found in :
(a) Stroma
(b) Lumen of thylakoids
(c) Intermembrane space
(d) Antenna complex
Solution :
Correct option : B According to chemiosmotic hypothesis, ATP synthesis is linked to the development of a proton gradient across the membrane of the thylakoid. The splitting of the water molecule takes place on the inner side of the membrane and so the hydrogen ions (protons) that are produced, they accumulate within the lumen of the thylakoids. So, the highest number of protons are found in lumen of thylakoids in chloroplast.