Which statement correctly describes a photoautotroph?

Prepare for the Microbial Metabolism Test. Utilize flashcards and multiple choice questions with helpful hints and detailed explanations. Ace your test with ease!

The main idea here is how a phototroph gets energy and carbon. A photoautotroph uses light energy to drive its metabolism and uses inorganic carbon, typically carbon dioxide, as its carbon source for building organic molecules. In photosynthesis, light powers the conversion of CO2 into sugars via pathways like the Calvin cycle, enabling these organisms to synthesize biomass from inorganic carbon. That combination—energy from light and carbon from CO2—is what defines photoautotrophy.

The other scenarios mix energy or carbon sources differently: using light for energy but organic carbon would describe a phototroph that is not autotrophic; using chemical energy would describe chemoautotrophs, and using chemical energy with organic carbon would be chemoorganotrophs.