SOL 3.6, Part 3 Living Systems
Page 1
Our Earth has many different environments. Some of these are water environments and some are dry-land. Each environment has its own climate, animals, and plants. There are two kinds of waterrelated environments: fresh water and salt water . Fresh water environments include ponds, marshes, swamps, streams, and rivers. Salt water environments include the Earth’s oceans.
Salt Water Environments
Seventy percent of the water on Earth is located in our four oceans. Ocean water is a mixture of gases like air and dissolved solids such as salts. This salty mixture supports many animals and plants. Let’s investigate!
Plants
T here are two main types of ocean plants: those that have roots and are attached to the ocean floor and those that do not have roots and simply float about on the surface of the water. Like the plants that live in dry-land environments, the plants of the ocean are producers and need sunlight to make their own food to survive.
This need for sunlight causes rooted ocean plants to live in coastal areas where waters are shallow.
Shallow water allows the rays of the sun to reach the plants. The most common rooted ocean plant is seaweed. Some seaweed, like the Giant Kelp, can grow to 125 feet in length.
The most abundant plants in the ocean are not attached to the ocean floor, however. These plants are called phytoplankton . Phytoplanktons are tiny floating plants that drift in the surface waters of the ocean. They remain near the surface because like seaweed, they need sunlight to survive. A bucket of sea water can hold a million of these tiny producers!
It’s Elementary! itselementary03@verizon.net
copyright 2004

SOL 3.6, Part 3 Living Systems
Page 2
(continued)
Animals
There are three main types of ocean animals. The first type of ocean animal floats about just like some ocean plants. These animals are unable to move through the water on their own, so the winds and currents carry them from place to place. One example of a floating ocean animal is the jellyfish.
The next type of ocean animal swims about freely. These animals live in all parts of the ocean environment from the shallow waters of the coast to the deep waters of the open ocean. They include such animals as whales, dolphins, sharks, octopus, squid, sting rays, and hundreds of different kinds of fish. Some ocean animals such as fish live and travel together in groups called schools . Such a group is also known as a population. A population is a group of organisms of the same kind that live in the same place.
The third kind of sea animal spends its life moving about on the ocean floor. This group includes lobsters, starfish, worms, snails, oysters, corals and sponges, just to name a few!
The plants and animals that live in the ocean form a community. A community is all of the populations that live together in one place.
It’s Elementary! itselementary03@verizon.net
copyright 2004