5. What is the primary factor limiting the growth of primary producers in marine ecosystems, such as phytoplan A. Predation by herbivores B. Sunlight availability C. Concentration of oxygen D. Availability of fish 6. Which of the following is an abiotic factor in the ocean?

5. The primary factor limiting the growth of primary producers in marine ecosystems, such as phytoplankton, is B. Sunlight availability. Sunlight is essential for photosynthesis, the process by which phytoplankton produce energy. In marine ecosystems, sunlight availability decreases with depth, limiting the growth of phytoplankton in deeper waters.<br /><br />6. An abiotic factor in the ocean is B. Temperature. Abiotic factors are non-living components of an ecosystem that can influence the living organisms within it. Temperature affects the metabolic rates of marine organisms, their growth, and their distribution. Other abiotic factors in the ocean include salinity, pH, and the concentration of dissolved oxygen.