Final answer:
The density in seawater is determined by temperature and salinity. These factors affect the ocean's buoyancy and circulation, as well as the marine organisms within it.
Step-by-step explanation:
Density in seawater is determined by temperature and salinity. These two factors greatly influence the density of seawater, which is a crucial concept in marine biology and oceanography. The density affects not only the buoyancy of objects in the ocean but also has implications for marine organisms and the circulation of ocean currents. Higher salinity means that the water is denser and heavier, while higher temperature typically makes water less dense. Factors such as phytoplankton population changes, the biomasses of natural mussel populations, and the influence of abiotic factors like salinity and temperature on life in freshwater biomes highlight the interconnection between physical properties and biological conditions in aquatic environments.