The structure and function of neurons

• Sensory neurons are found in receptors such as the eyes, ears and skin, and carry nerve impulses to the spinal cord and brain
• Relay neurons are found in the brain and spinal cord and allow sensory and motor neurons to communicate.
• Motor neurons are found in the central nervous system (CNS) and control muscle movements. When motor neurons are stimulated they release neurotransmitters that bind to the receptors on muscles to trigger a response, which lead to movement
• Structure of Neurons

  A) Sensory

  B) Relay

  C) Motor

  D) Axon

  E) Myelin Sheath

  F) Dendrites

  
• The dendrites receive signals from other neurons or from sensory receptor cells. The dendrites are typically connected to the cell body, which is often referred to as the ‘control centre’ of the neuron, as it’s contains the nucleus.
• The axon is a long slender fibre that carries nerve impulses, in the form of an electrical signal known as action potential, away from the cell body towards the axon terminals, where the neuron ends. Most axons are surrounded by a myelin sheath (except for relay neurons) which insulates the axon so that the electrical impulses travel faster along the axon.
• The axon terminal connects the neuron to other neurons (or directly to organs), using a process called synaptic transmission.