In purple and green sulphur bacteria, the hydrogen donor is

In the green sulphur bacteria the hydrogen donor is H2S and the process of pigment is called ________ .

Assertion: In green plants H_(2)O is the hydrogen donor and is oxidised to O_(2) Reason: In the purple and green sulphur bacteria, the oxidation product is sulphur or sulphate depending on the organism and not O_(2) .

Write one green sulphur bacterium .

Who, after conducting experiments on purple and green sulphur bacteria, inferred that O_(2) evolved during photosynthesis comes from H_(2)O not from CO_(2) ?