Nerves are bundles of axons in the peripheral nervous system (PNS) that act as information highways to carry signals between the brain and spinal cord and the rest of the body

The human eye is a sense organ that reacts to light and allows vision. Rod and cone cells in the retina allow conscious light perception

The brain is arguably the most important organ in the human body. It controls and coordinates actions and reactions, allows us to think and feel, and enables us to have memories and feelings—all the things that make us human

The ear is a complex and delicate organ. It collects sound waves so you can hear the world around you. The ear also has a second function—it helps you keep your balance.