Question

Photo lithotrophic autotroph organisms use

• A. Light energy, inorganic electron source and CO\(_2\) as its carbon source
• B. Chemical energy, organic electron source and CO\(_2\) as its carbon source
• C. Light energy, organic electron source and organic compounds as its carbon source
• D. Chemical energy, inorganic electron source and CO\(_2\) as its carbon source

Hint:

• Breakdown of metabolic classification terms:
  • Energy: Photo- (light), Chemo- (chemical).
  • Electrons: -litho- (inorganic), -organo- (organic).
  • Carbon: -autotroph (CO\(_2\)), -heterotroph (organic C).
• Plants are photolithoautotrophs (using H\(_2\)O as the electron donor).

Answer 1

The Correct Option is A

Photo lithotrophic autotrophs are organisms that derive their energy from light and their electrons from inorganic sources. They utilize carbon dioxide (CO₂) as their carbon source to carry out the process of photosynthesis. This specific type of autotroph plays a crucial role in ecosystems as primary producers.

The components involved in the metabolic processes of photo lithotrophic autotrophs can be broken down as follows:

• Light Energy: They harness energy from light through photosynthetic pigments, such as chlorophyll, to drive biochemical reactions necessary for survival and growth.
• Inorganic Electron Source: These organisms typically use water (H₂O) or other inorganic compounds, such as hydrogen sulfide (H₂S), as electron donors. The electrons are crucial for the reduction of carbon dioxide during photosynthesis.
• CO₂ as Carbon Source: Carbon dioxide is fixed into organic molecules through the Calvin cycle, producing carbohydrates that serve as cellular energy and organic compounds.

Given these characteristics, the correct description of photo lithotrophic autotrophs is: Light energy, inorganic electron source and CO₂ as its carbon source.