A millibar is a unit of pressure which is most commonly seen in the context of meteorology, where atmospheric pressure is sometimes given in millibars. As the name would suggest, a millibar is equal to one thousandth of a bar.
User: The microscopic organisms at the base of the marine food chain are known as A. plant life. B. terrestrial animals. C. primitive life. D. phytoplankton. Weegy: The microscopic organisms at the base of the marine food chain are known as Phytoplankton. User: In addition to being necessary for respiration, _______ also provides UV radiation protection. A. water B. hydrogen C. oxygen D. carbon dioxide.
Plankton are drifting organisms in aquatic environments, including marine and fresh water. They are the base of the food web in these environments. Plankton can be divided into broad functional groups: 1  Phytoplankton are microscopic plants that form the base of the marine food chain.2  Though they are small, the energy they capture from the sun through photosynthesis helps to sustain almost all life in the ocean.oplankton also need iron in their diet. So, that is also where zooplankton can be found; the top 100 meters of the water to be exact. Just like phytoplankton, zooplankton can't swim; instead they just float along with the currents, tides and and winds.