The primary producers of the deep sea hydrothermal vent

SOLUTION

Life is typically sparse on the deep seafloor, where organisms endure high pressure, near-freezing temperatures and pitch-black darkness. But at certain spots on the ocean floor where tectonic plates meet, unique ecosystems teem with unusual animal species. There, mineral-laden fluid is emitted either as a warm (5-100 degrees Celsius/41-212 degrees Fahrenheit), diffuse flow from seabed cracks or as plumes of superheated water (250-400 degrees Celsius/482-752 degrees Fahrenheit) from chimney-like structures. These structures are referred to as hydrothermal vents. 
Most bacteria and archaea cannot survive in the superheated hydrothermal fluids of the chimneys or “black smokers.” But hydrothermal microorganisms are able to thrive just outside the hottest waters, in the temperature gradients that form between the hot venting fluid and cold seawater. These microbes are the foundation for life in hydrothermal vent ecosystems. Instead of using light energy to turn carbon dioxide into sugar like plants do, they harvest chemical energy from the minerals and chemical compounds that spew from the vents—a process known as chemosynthesis. These compounds—such as hydrogen sulfide, hydrogen gas, ferrous iron and ammonia—lack carbon. So the primary producers of hydrothermal vents are chemosynthetic bacteria.