Ecosystems based on chemoautotrophic prokaryotes occur around deep-sea hydrothermal vents at 2,500 m below the ocean surface.These bacteria
A) obtain energy from sunlight.
B) obtain energy as endoparasites of giant worms.
C) obtain energy by oxidizing hydrogen sulfide.
D) oxidize organic compounds for energy.
E) obtain energy by reducing heavy metals.

Question

Quizplus · Accepted Answer

Chemoautotrophic prokaryotes at deep-sea hydrothermal vents obtain their energy by oxidizing hydrogen sulfide, which is released from the vents along with other chemicals. This process is known as chemosynthesis. They do not obtain energy from sunlight (choice A), as they are found in the deep ocean where sunlight does not reach. They are not endoparasites of giant worms (choice B) or reduce heavy metals (choice E). While some deep-sea bacteria may oxidize organic compounds for energy (choice D), the specific bacteria at hydrothermal vents obtain their energy through the process of chemosynthesis.

Ecosystems Based on Chemoautotrophic Prokaryotes Occur Around Deep-Sea Hydrothermal Vents