2 Minute Neuroscience: The Neuron

Overview

• Neurons are the primary functional units of the nervous system.
• The brain contains approximately 85 billion neurons.
• Neurons vary in shape and size, but a common textbook representation is used for explanation.

Structure of a Neuron

Dendrites

• Dendrites resemble tree branches and are extensions from the neuron.
• Primary function is to receive information from other neurons.
• Contain receptors for neurotransmitters, which are chemicals that carry signals.

Soma (Cell Body)

• Houses the nucleus, which contains the cell's DNA.
• Integrates signals received from dendrites.

Axon Hillock

• The area where the soma integrates signals and determines if they're strong enough to pass on.

Axon

• If the signal is strong enough, it becomes an action potential.
• The axon is a long, thin structure that transmits the action potential away from the soma.
• Covered with myelin, an insulating material that prevents signal degradation.

Axon Terminals (Synaptic Buttons)

• The endpoint of an axon where the action potential arrives.
• Triggers the release of neurotransmitters.

Neurotransmission

• Neurotransmitters are released from axon terminals and interact with receptors on dendrites of adjacent neurons.
• This interaction stimulates the next neuron, continuing the process of signal transmission across the nervous system.