The body is comprised of various systems supported by organs. The heart supports the circulatory system by pumping blood to all parts of the body. The lungs in the respiratory system facilitates air exchange. There are various other systems in the body, but the primary system psychologists focus on is the nervous system.
Every system is made up of cells, the basic building blocks of multicellular life.
Each cell is a self-contained unit enclosed by a membrane, or layer that allows materials to go into and out of the cell. There are many types of cells throughout the body that each have a specialty or function. For example, red blood cells of the circulatory system are specialized to carry oxygen. The cells of the nervous system are called neurons , cells specialized for transmitting and receiving information. The axon is long, wispy structure that sends electrical signals to destination neurons.