Life in the Ocean

3 Major Groups of Marine Life Plankton Float at or near the surface of ocean Two types: Phytoplankton – plant like Zooplankton – animal like Nekton Free swimming organisms: Dolphins Benthos Live on the ocean floor: clams, crabs

Ocean Zones Three Ecological Zones Intertidal Neritic Open-ocean

Intertidal Zone Extends from the High tide to the Low Tide Drastically changing environment Why? Periods of underwater, exposed to sunlight and air, pounding of waves, and change in temp and salinity Organisms adapt to live underwater and on land Shells = protection: sunlight and tides

Neritic Zone Begins at the low-tide limit and extends to edge of continental shelf Temp, pressure, nutrients and sunlight are consistent Majority of organisms found within the upper 100 meters. Why? Algae grows providing food and shelter

Open-ocean Zone Extends from shelf to Deep Ocean Basin Contains water column: Surface to deep Plant life is scarce due to lack of sunlight Water has few nutrients Colder temps and higher pressure lead to interesting adaptations