Online College Courses for Credit



Author: Nathan Lampson

This lesson will illustrate the unique characteristics of oceans and oceanic life.

See More

As the largest of all ecosystems, oceans occupy much of the earth's surface.  This lesson will discuss the characteristics of the ocean ecosystem.



An estuary is an area of the ocean where freshwater from a river or stream mixes with the salt water of the ocean.


Coral Reefs

Coral Reefs are complex ecosystems found along land formations.  In warm shallow waters, coral thrive and produce communities of organisms.  The Great Barrier Reef is an example of a coral reef found off the coast of Australia.


Continental Shelf

The shallow area of ocean surrounding a land mass is called a continental shelf.



A type of algae that can use sunlight in order to produce energy.  Phytoplankton are one the main oxygen producers on the planet earth.



Zooplankton are tiny organisms that consume phytoplankton and provide energy to many small fish species.

Marine Mammals

Marine mammals are the largest mammals on earth.  The blue whale can grow to be almost 100ft long.

Dolphins are among the world's most intelligent animals.  Whales and dolphins both live in pod communities and are thought to be very social animals.

Benthic Zone

The ocean floor is called the benthic zone.  Many species of invertebrates live in the benthic zone.


Pelagic Zone

The open ocean is known as the pelagic zone.  


Aphotic Zone

The portion of the ocean that receives no sunlight from the sun is known as the aphotic zone.


Intertidal Zone

The intertidal zone is found where the ocean meets the land.  The level of the ocean constantly changes causing the intertidal zone to be a biological community.



The level of the sea rises and falls due to the moon's gravity.  The rise and fall of sea level is known as the tide.