Animal Characteristics Heterotrophic – obtain food and energy by feeding Multicellular – made of many cells Eukaryotic – contain a nucleus Vertebrates – 5% of all animals Invertebrates – 95 % of all animals

Types of Animal tissues 4 Types 1. Epithelial – skin 2. Muscular - muscles 3. Connective –blood and bone 4. Nervous – nerve cells

Essential Animal Functions 1. Feeding Herbivores - manatee Carnivores – sharks, sea anemones Omnivores Detritivores – most bottom dwellers Filter feeders – sponges, clams, oysters 2. Respiration Take in oxygen and give off carbon dioxide. Many inverterbrates do this by diffusion. Complex animals use gills or lungs.

Animal Functions, cont’d. 3. Circulation – how materials move around the animal. (diffusion or circulatory systems) 4. Excretion – removal of waste. Could be cells that pump waste out or organs. Waste is ammonia 5. Response – nerve cells. This could be a simple nerve net or complex nervous system. 6. Movement – some animals are sessile – stay attached to something their adult life. Others are motile – move by muscles or muscle-like tissue. 7. Reproduction – sexual or asexual. Many simple animals have the ability to do both.

Body Symmetry Asymmetrical – no body plan Ex. Sponges Radial symmetry – body parts repeat around the center. Ex. starfish Bilateral symmetry – body can be divided up into two equal halves (left and right) Ex. whale

Cephalization – concentration of the sense organs at the front end of an animal. Not all animals show this.