Neurons and Their Function

Overview

• Neurons are the primary functional units of the nervous system.
• The human brain contains approximately 85 billion neurons.

Structure of a Neuron

• Dendrites:
  • Appear like tree branches.
  • Main area where neurons receive information.
  • Receptors on dendrites pick up chemical signals (neurotransmitters) from other neurons.
• Soma (Cell Body):
  • Contains nucleus and the cell's genetic material (DNA).
  • Integrates information from dendrites.
• Axon Hillock:
  • Integrates signals from dendrites.
  • If the signal is strong enough, it initiates an action potential.
• Axon:
  • Transmits the action potential.
  • Insulated with myelin to prevent signal degradation.
• Axon Terminals (Synaptic Buttons):
  • End part of the neuron where the signal causes the release of neurotransmitters.

Signal Transmission

• Action Potential:
  • A signal initiated at the axon hillock and travels down the axon.
• Neurotransmitter Release:
  • Occurs at axon terminals.
  • Neurotransmitters interact with the receptors on the dendrites of the next neuron, continuing the transmission process.