Your eyes help you see. Light goes into your eye. It goes through an opening called the pupil. The iris is the colored part of the eye.

Your pupils get smaller in bright light. They open wider in dim light. The retina is a light-sensitive layer. It is at the very back of the eye.

Sound waves go into your ears. They make your eardrums vibrate. The pinna is the part of the ear you can see. It is on the side of your head.

Your nose lets you smell. Smell helps you taste, too. Without smell, foods taste bland.

You use your tongue to taste. The small bumps on your tongue are called papillae. They hold your taste buds.

You may have heard there are only four tastes. In fact, taste buds can detect five flavors. They are sweet, sour, bitter, salty and umami (savory).

Skin is the body's largest organ. Your skin has nerve endings. They let you feel hot, cold and touch.

Your fingers can read, too. Braille is a way of reading with the fingers. It uses raised dots.

ASL is American Sign Language. It is the primary language of many North Americans. They are deaf or hard of hearing. It is expressed by movements of the hands and face.

Your senses send messages to your brain. Your eyes help you see. Your nose lets you smell. You use your tongue to taste.

Words to know

• pupil: eye opening
• retina: back of eye
• papillae: tongue bumps
• umami: savory taste
• braille: raised dots