jaryd+tarpenning

Though there is great diversity in the animal kingdom, animals can be distinguished from the other kingdoms by a set of characteristics. Though other types of life may share some of these characteristics, the set of characteristics as a whole provide a distinction from the other kingdoms. A set of characteristics are provided Animals are multicellular. Animals are heterotrophic, obtaining their energy by consuming energy-releasing food substances. Animals typically reproduce sexually. Animals are made up of cells that do not have cell walls. Animals are capable of motion in some stage of their lives. Animals are able to respond quickly to external stimuli as a result of nerve cells, muscle or contractile tissue, or both.

 Our planet is in trouble! Almost every day we seem to hear of yet another problem affecting the environment - and what a list of problems! - pollution, acid rain, climate change, the destruction of rainforests and other wild habitats, the decline and extinction of thousands of species of animals and plants....and so on.Nowadays, most of us know that these threats exist and that humans have caused them. Many of us are very worried about the future of our planet and unless we can find a way of solving the problems we have made then the environment will suffer even more.  Mollusks The phylum Mollusca is the largest and most diverse phylum of animals next to arthropods. Mollusks can be found in nearly every ecosystem on earth, from high, barren mountains to grassy plains, lakes, rivers and in all seas and oceans. There are nearly 100,000 species of mollusks identified today, with new species being encountered and named every year as new discoveries are made in ocean depths and tropical rainforests. The body of a mollusk is generally composed of the shell and the fleshy, living part. The fleshy parts of a mollusk can be further divided into the foot and the visceral mass. The foot is a distinctive molluscan feature, adapted in a variety of ways for locomotion. The visceral mass includes the organs for digestion, circulation, reproduction, and respiration. The visceral mass also includes two external flaps of tissue called the mantle, which secretes the calcareous shell and encloses a mantle cavity. The fluid in the mantle cavity, which in aquatic mollusks is continually replaced with water from the outside, carries away excess water, ions and wastes, and helps circulate nutrients and oxygen. Another structure unique to mollusks, found in most groups except bivalves and a few others is the radula. In most forms the radula is a rasping organ near the mouth variously modified for special feeding techniques.
 * Arthropods

**What is an arthrpod?** The arthropods constitute over 90% of the animal kingdom and are classified in the phylum Arthropoda. They are distinguished from other animals by: Grasshoppers, butterflies, beetles, ants, etc. 1,000,000 described world species
 * an exoskeleton (a skeleton on the outside of the body)
 * body divided into distinct parts
 * jointed legs and appendages
 * bilateral symmetry (both sides of the body are the same) ||
 * **Class Distinctions** **Insects**


 * three body regions: head, thorax, abdomen
 * six legs attached to the thorax (which has 3 segments)
 * adults with one or two pairs of wings attached to the thorax (some have none)
 * two antennae
 * lateral compound eyes ||

Echinoderms 

Echinoderms are characterized by radial symmetry, several arms (5 or more, mostly grouped 2 left - 1 middle - 2 right) radiating from a central body (= pentamerous). The body actually consists of five equal segments, each containing a duplicate set of various internal organs. They have no heart, brain, nor eyes, but some brittle stars seem to have light sensitive parts on their arms. Their mouth is situated on the underside and their anus on top (except feather stars, sea cucumbers and some urchins). Echinoderms have tentacle-like structures called tube feet with suction pads situated at their extremities. These tube feet are hydraulically controlled by a remarkable vascular system. This system supplies water through canals of small muscular tubes to the tube feet (= ambulacral feet). As the tube feet press against a moving object, water is withdrawn from them, resulting in a suction effect. When water returns to the canals, suction is released. The resulting locomotion is generally very slow.

Aves

The vertebrate class Aves includes the birds, an extremely distinctive and successful clade, with an estimated 9000 species worldwide, including the snowy owl pictured here. Although descended from the dinosaurs, birds have evolved remarkable specializations for flight: a unique "one-way" breathing system, light yet strong hollow bones, a skeleton in which many bones are fused or lost, powerful flight muscles, and -- most importantly -- feathers.

<span style="margin-bottom: 0.5em; margin-left: 0px; margin-right: 0px; margin-top: 0.5em; text-align: justify;"><span style="-webkit-border-horizontal-spacing: 1px; -webkit-border-vertical-spacing: 1px; border-collapse: separate; color: #000000; font-family: Tahoma,'Franklin Gothic Medium',Arial; font-size: 13px;">Works Cited <span style="-webkit-border-horizontal-spacing: 1px; -webkit-border-vertical-spacing: 1px; border-collapse: separate; color: #000000; font-family: Tahoma,'Franklin Gothic Medium',Arial; font-size: 13px;"> [] [] [] [] []