Nerve

• Nerve Cells - transmit electrical and chemical signals.
• There are three main types of neurons:

  • sensory neurons - receive signals from sensory receptors in the body and transmit them to the brain or spinal cord.
  • motor neurons - transmit signals from the brain or spinal cord to muscles or glands.
  • Interneurons - connect sensory and motor neurons and are responsible for processing and integrating information.
• KEY NOTES

  • Synapse: The junction between two neurons or between a neuron and a target cell (like a muscle cell).
  • Neurotransmitters: Chemicals released at the synapse that transmit signals from one neuron to another.
  • Action potential: A rapid change in a neuron's electrical charge when stimulated, triggering neurotransmitter release and signal transmission.
• KEY NOTES

  • Myelin: A fatty substance that insulates and surrounds some neuron axons, increasing the speed and efficiency of signal transmission.
  • Plasticity: The ability of neurons to change and adapt in response to experience or injury, allowing the brain to reorganize and form new connections.
• A nerve cell/neuron consists of three main parts:

  • Cell body - contains the nucleus and other organelles
  • Dendrites – short branching extensions that receive signals from other neurons
  • Axon - long, thin extension that transmits signals away from the cell body.