Question

The experiment material used by Van Neil, to prove that $O_2$ comes out from water was studied on

• A. Chlorella pyrenoidosa
• B. Cladophora
• C. purple & green sulphur bacteria
• D. blue green algae

Answer 1

Answer: (C)

By studying purple sulphur bacteria and green sulphur bacteria, Cornelius Van Niel was the first scientist to demonstrate that photosynthesis is a light-dependent redox reaction in 1931, in which hydrogen from an oxidizable compound reduces carbon dioxide to cellular materials. This can be expressed as: $2H_{2}A+C{O}_2\to 2A+C{H}_{2}O+$ $H_{2}O$, where $A$ is the electron acceptor. His discovery predicted that $H_{2}O$ is the hydrogen donor in green plant photosynthesis and is oxidized to $O_2$.