In non-cyclic photophosphorylation,how many protons $(H^+)$ are released into the lumen of the thylakoid for the photolysis of $2$ molecules of $H_2O$ (in $H^+$)?

Which of the following is the byproduct of photosynthesis?

What are the important events and end products of the light reaction?

Which of the following products of photosynthesis is produced first?

The following $(I-VI)$ are the main steps of chemiosmotic $ATP$ synthesis in the light reaction. Arrange them in the correct order:
$I$. $H^+$ concentration gradient established
$II$. $H^+$ diffuses through $ATP$ synthase
$III$. Carriers use energy from electrons to move $H^+$ across the membrane
$IV$. Electrons from $PS-II$ pass along the electron transport chain
$V$. Light excites electrons in $PS-II$
$VI$. Energy of $H^+$ flow is used by $ATP$ synthase to make $ATP$

Which of the following is not required for chemiosmosis in chloroplast?