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PLANTS

Sea Anemones

Sea Cabbage

ANIMALS

Mollusks

CrustaceansSea Anemones

The ornately colored sea anemone (uh-NEM-uh-nee) is named after the equally flashy terrestrial anemone flower. A close relative of coral and jellyfish, anemones are stinging polyps that spend most of their time attached to rocks on the sea bottom or on coral reefs waiting for fish to pass close enough to get ensnared in their venom-filled tentacles. Their bodies are composed of an adhesive pedal disc, or foot, a cylindrical body, and an array of tentacles surrounding a central mouth. The tentacles are triggered by the slightest touch, firing a harpoon-like filament into their victim and injecting a paralyzing neurotoxin. The helpless prey is then guided into the mouth by the tentacles.

There are more than 1,000 sea anemone species found throughout the worlds oceans at various depths, although the largest and most varied occur in coastal tropical waters. They run the full spectrum of colors and can be as small as half an inch (1.25 centimeters) or as large as 6 feet (1.8 meters) across.Sea GrassesThese unusual marine flowering plants are calledseagrassesbecause in many species the leaves are long and narrow, grow by rhizome extension, and often grow in large "meadows", which look like grassland: in other words, many of the species of seagrasses superficially resemble terrestrialgrassesof the familyPoaceae. Seagrasses form extensive beds or meadows, which can be either monospecific (made up of a single species) or in mixed beds where more than one species coexist. Intemperateareas, usually one or a few species dominate (like the eelgrassZostera marinain the North Atlantic), whereastropicalbeds usually are more diverse, with up to thirteenspeciesrecorded in thePhilippines.

Crustaceans

Crustaceans have adapted to water through various morphological, physiological, biochemical, and behavioral modifications, of which some are shared by all land-dwelling crustaceans and others are unique to animals within a particular habitat. Among the three groups of crustaceans having truly terrestrial members, the amphipods have achieved their success on land primarily by behavioral means, while the isopods and the decapods have developed many morphological, physiological, and biochemical adaptations as well.

Mollusks

Members of the mollusk family have no body segmentation. Instead, their bodies are divided into three body regions: the head, visceral mass, and a "foot." The head of a mollusk contains all the sensory organs and the brain. The visceral mass contains the internal organs. Mollusks also have a foot-like part of their body. This "foot" is a tough part of tissue used to propel them along the substrate on which they live. Mollusks usually have shells, though some do not. The shell is secreted by a region of the body known as the mantle. Many mollusks also have a radula. The radula is akin to a tongue. It is rough and used to scrape at and eat food. The mollusks family is divided into seven groups, the most common being Gastropods, Bivalves, Chitons, and Cephalopods.