Question

The purple sulphur bacteria use hydrogen sulphide and
release sulphur but not oxygen. Which of the following
agrees with above observation

• A. The $H_2$ that reduces $C{O}_2$ comes from $H_{2}S$ that liberates sulphur
• B. photosynthesiss does not require chlorophyll
• C. Photosynthesis consist of a light and a dark reaction
• D. The $H_2$ which reduces $C{O}_2$in photosynthesis comes from $H_{2}O$ that releases $O_2$

Answer 1

The correct option is A The $H_2$ that reduces $C{O}_2$ comes from $H_{2}S$ that liberates sulphur

$6C{O}_2+12H_{2}S\stackrel{Light}{\to }{C}_2{H}_{12}{O}_6+12S+6H_{2}O+$ energy.
Here $H_{2}S$ utilized as a source of hydrogen, which reduces
$C{O}_2$ into glucose. Oxygen is not liberated in
bacterial photosynthesis