Final answer:
Terrestrial plants primarily utilize atmospheric carbon dioxide for photosynthesis, but in aquatic environments, bicarbonate (HCO−) can also serve as a carbon source. This is especially true for marine plants and algae that are adapted to use dissolved inorganic carbon compounds.
Step-by-step explanation:
The question is regarding whether terrestrial plants use bicarbonate (HCO−) as a carbon source for photosynthesis. The answer is TRUE. Terrestrial autotrophs primarily obtain their carbon from atmospheric carbon dioxide; however, in aquatic environments, where carbon dioxide can also be in the form of dissolved compounds, marine plants and algae can utilize bicarbonate (HCO3−) for photosynthesis. Notably, in these environments, bicarbonate can be in equilibrium with dissolved CO2, which further substantiates its role as a viable carbon source.
During the photosynthesis process, carbon dioxide combines with water to form carbonic acid (H2CO3), which can disassociate into bicarbonate and then into carbonate ions. These compounds can be used by marine photosynthetic organisms to fix carbon into organic compounds such as glucose.