Which of the following marine phototrophs can utilise carbon-dioxide as the carbon source?
Which of the following marine phototrophs can utilise carbon-dioxide as the carbon source?
Select an option to attempt
Correct Answer: Option B
Explanation
Green sulfur bacteria (family Chlorobiaceae, e.g. Chlorobium tepidum) are obligate anaerobic photoautotrophs. They use sunlight as energy source, inorganic sulfur compounds (,,) as electron donors, andas their sole carbon source (autotrophs). They fixvia the reverse TCA (reductive citric acid) cycle, not the Calvin cycle. They contain bacteriochlorophyll c, d, or e in chlorosomes (light-harvesting antenna). Heliobacteria use organic carbon; Halobacteria (Archaea) use bacteriorhodopsin and are heterotrophic; Chloroacidobacteria are a recently discovered minor group.