The morphology of neurons makes them highly specialized to work with neural impulses; they generate, receive and send these impulses onto other neurons and non-neural tissues.
There are two types of neurons, named according to whether they send an electrical signal towards or away from the CNS;
- Efferent neurons (motor or descending) send neural impulses from the CNS to the peripheral tissues, instructing them how to function.
- Afferent neurons (sensory or ascending) conduct impulses from the peripheral tissues to the CNS. These impulses contain sensory information, describing the tissue’s environment.
The site where an axon connects to another cell to pass the neural impulse is called a synapse. The synapse doesn’t connect to the next cell directly. Instead, the impulse triggers the release of chemicals called neurotransmitters from the very end of an axon. These neurotransmitters bind to the effector cell’s membrane, causing biochemical events to occur within that cell according to the orders sent by the CNS.