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.
Phytoplankton is the base of several aquatic food webs. In a balanced ecosystem, they provide food for a wide range of sea creatures including whales, shrimp, snails, and jellyfish. Phytoplankton, also known as microalgae, are similar to terrestrial plants in that they contain chlorophyll and require sunlight in order to live and grow. Most phytoplankton are buoyant and float in the upper part of the ocean, where sunlight penetrates the water. Phytoplankton also require inorganic nutrients such as nitrates, phosphates, and sulfur which they convert into proteins, fats, and carbohydrates. The two main classes of phytoplankton are dinoflagellates and diatoms.