The nervous sytem is a complex collection of nerves and specialized cells known as neurons that transmit signals between different parts of the body. The nervous system has two components:
The central nervous system is made up of the brain, spinal cord, and nerves. The peripheral nervous system consists of sensory neurons, ganglia (cluster of neurons), and nerves that connect to one another and to the central nervous system. Neres are cylindrical bundles of fibers that start at the brain and central cord and branch out to every other part of the body. Neurons are what send signals to other cells through thin fibers called axons, which cause synapses (neurotransmitters) to be released at the synpatic cleft. An interesting fact is that the brains of highly creative people have more connections among three specific regions of the brain than less creative thinkers. Sensory neurons react to physical stimuli such as light, sound, and touch and send feedback to the central nervous system or in peripheral ganglia, transmit signals to activate the muscles or glands. Glial cells are specialized cells that support, protect or nourish nerve cells.
Here are all of the main organ systems of the human body and some info about them: