Question

Question 07
During light reaction in photosynthesis the following are formed
(a) ATP and sugar (b) hydrogen, $O_2$ and sugar
(c) ATP , hydrogen donor and $O_2$ (d) ATP, hydrogen and $O_2$ donor

Answer 1

(c) Light dependent reaction uses solar power to generate ATP and $NADP{H}_2$ which provide chemical and reducing power respectively to sugar synthesising reaction of the Calvin cycle, while the $O_2$ in released as a by product of light dependent reaction. Other options are incorrect because
(a) ATP is produced in light reaction but sugar is produced in dark reaction.
(b) $H_2$ is produced by splitting of water $(H_{2}O\to 2H^{+}+\frac{1}{2}{O}_2)H^{+}$ are released. The $2H^{+}$ is accepted by NADP to form NADPH and oxygen $\left(O_2\right)$ is of course produced but sugar is not.
(c) $O_2$ donor and ATP is produced in light reaction but not the hydrogen.