Neurons vary widely in size and shape depending on their location and function. However, they all contain the same three key structural components – a cell body, an axon, and dendrites. 

1. Cell Body - Each neuron has a cell body, which holds the nucleus, endoplasmic reticulum, Golgi body, and mitochondria. Protein synthesis takes place in the endoplasmic reticulum within the cell body. 
2. Axon - The axon is a long, slender, tubular structure that extends from the cell body. It is coated in a layer of myelin, which is essentially a layer of cells wrapped around the axon. The axon carries electrical or nerve impulses from the cell body and transmits them to the axon terminals, from where they are passed on to an adjacent neuron. Axon terminals are the most distal portions of the axon. They act as the point of transmission, sending chemical signals from the neuron to other cells usually via transmitter release. 
3. Dendrites - Dendrites are elongated branch-like structures that extend outward from the cell body. They receive input from the environment and other neurons and transmit these messages to the cell body.