Which organism constitutes more than 99% of the plants produced in the oceans?

Phytoplankton are microscopic organisms that play a crucial role in ocean ecosystems and are indeed responsible for producing more than 99% of the organic matter derived from photosynthesis in marine environments. They are the foundation of the aquatic food web and are vital for the overall health of the ocean.

Phytoplankton, like diatoms and cyanobacteria, utilize sunlight and carbon dioxide in the process of photosynthesis, generating oxygen and organic compounds. This process not only supports their own growth but also sustains a wide array of marine life, including larger organisms such as fish and whales, which rely on these tiny plants as their primary food source.

In contrast, while corals, grasses, and seaweeds contribute to marine life and some have significant ecological roles, they do not match the vast scale of production that phytoplankton achieves in ocean environments. Corals are primarily animals with symbiotic relationships with algae, marine grasses (like seagrasses) are limited to specific coastal areas, and seaweeds, although important, do not surpass the productivity of phytoplankton. Thus, the dominance of phytoplankton in marine photosynthesis and their crucial role in oceanic ecosystems emphasize why they are recognized as the primary