Animals can have four main kinds of parts. Each part helps it survive in some way.

• Parts that support and protect: these include skin, shells, feathers, scales, and bones.
• Parts that move: arms, legs, wings, and fins are moving parts.
• Parts that get information: eyes, ears, skin, noses, and tongues gather information.
• Parts that take in materials: mouths, noses, skin, and other openings in organisms can take in materials.

Body parts are made of smaller parts. These smaller parts work together in systems. A system is a group of parts that work together.

Bones and muscles form a system that supports your body and helps animals move. Being able to move helps animals survive. Moving parts help animals get food, escape from danger, and build or find homes. Different body parts collect different information. Eyes get light information. Ears receive sounds. The skin gets information from touch.

Some parts of animals take in materials to get energy. Animals take in food and oxygen. Animals breathe gases in and out through lungs or gills. Most large organisms also have liquid and solid wastes. Special systems in their bodies get rid of these wastes.