Answer
d. at hydrothermal vents
Work Step by Step
Chemoautotrophic bacteria and archaea are organisms that obtain energy by oxidizing inorganic compounds, such as hydrogen sulfide or methane, rather than relying on sunlight for energy like most other organisms do through photosynthesis. These organisms are typically found in environments where sunlight is scarce or absent, such as deep-sea hydrothermal vents.
Hydrothermal vents are fissures in the ocean floor where geothermally heated water emerges. These vents release a variety of inorganic compounds, including hydrogen sulfide and methane. Chemoautotrophic bacteria and archaea present in the vicinity of these vents use these compounds as energy sources to produce organic matter through chemosynthesis.
Because sunlight cannot penetrate to these depths in the ocean where hydrothermal vents are located, chemoautotrophic bacteria and archaea form the base of the food chain in these ecosystems. They are the primary producers, converting inorganic compounds into organic matter that other organisms in the vent community can utilize for energy. Therefore, hydrothermal vents are an example of an ecosystem where chemoautotrophic bacteria and archaea serve as the primary producers for the food web.
