GEOLOGY

Detailed explanation-1: -With 71% of the Earth covered by the ocean, phytoplankton are responsible for producing up to 50% of the oxygen we breathe. These microscopic organisms also cycle most of the Earth’s carbon dioxide between the ocean and atmosphere. Zooplankton are the animal-like primary consumers of plankton communities.

Detailed explanation-2: -Prochlorococcus and other ocean phytoplankton are responsible for 70 percent of Earth’s oxygen production.

Detailed explanation-3: -These organisms include bacteria, algae and plants. Photosynthesizing algae in the ocean produce around 70% of oxygen in the atmosphere.

Detailed explanation-4: -In the open ocean, bacterial and cyanobacterial communities are dominated by nonmotile cells of two ubiquitous species: Prochlorococcus marina and Pelagibacter ubique. P. marina is Earth’s smallest free-living phototroph (that is, it uses light for energy to fix carbon dioxide into organic matter).

Detailed explanation-5: -The ocean. Plants, algae, and cyanobacteria all create oxygen. They do this through photosynthesis. Using energy from sunlight, they turn carbon dioxide and water into sugar and oxygen.