The human brain alone contains around 100 billion neurones
Neurones are the body’s communication system, they send short bursts of electricity at 119 metres per second (that’s 266 mph), as a way to pass messages between the brain and body. They are involved in movement including reflexes, our senses and all complex thought and memory.
Neurons are responsible for passing information around the central nervous system (CNS) and from the CNS to the rest of the body. Each nerve cell comprises a body (top) surrounded by numerous extensions called dendrites. Dendrites collect information from other nerve cells or from sensory cells. Each neuron also has one process called an axon (bottom), which passes information to other nerve cells, or to effector cells such as muscle fibres. The axon appears segmented as it is surrounded by a myelin sheath, which contains gaps, called nodes of Ranvier. The myelin insulates the axon, allowing signals to be transmitted more quickly. The axon terminates with motor end plates which typically stimulate muscle cells.