Question

Which is correct for bacteria?

• A. They have both cyclic and non-cyclic photo phosphorylation
• B. They absorb light > 900 nm of wavelength
• C. They release $ {{\text{O}}_{\text{2}}} $ during photosynthesis
• D. They use $ {{\text{H}}_{\text{2}}}\text{O} $ during photosynthesis

Answer 1

Answer: (B)

Photosynthetic bacteria contain bacterial chlorophyll as a light trapping pigment molecule that absorbs light between 800 to 925 nm, depending on the species of bacteria. Bacterial photosynthesis occurs without evolution of $ {{\text{O}}_{2}} $ (it is anoxygenic process) as water $ ({{H}_{2}}O) $ is not used as hydrogen donor. Instead of $ {{\text{H}}_{\text{2}}}\text{,}\,\,{{\text{H}}_{\text{2}}}\text{S} $ and other similar compounds are employed as the electron donor. Bacteria have only one pigment system similar to that of $ \text{PS}-\text{I} $ thus, only cyclic photophosphorylation occurs in hotosynthetic bacteria.