New Impulses

• A brief, large change in membrane potential during which the potential reserves so that the inside the cell rapidly and briefly becomes more positive than outside?

  Action Potential
• Neurons send messages electrochemically
• Nerve cells have a semi-permeable membrane
• Important Ions:

  • Sodium
  • Potassium
  • Calcium
  • Chlorine
• Nerve and muscles are excitable tissue
• Membrane potential becomes less negative during depolarization
• Membrane potential becomes more negative during hyperpolarization
• Electrical signals are produced by changes in ion movement across the plasma membrane
• Once a signal is received, the nodes will bring sodium in, and allow potassium out. This is the?

  Ion Exchange
• The ion exchange cascades down the axon, exchanging ions one node after another, until it reaches the axon terminals
• At the axon terminal, neurotransmitters are released to excite other cells
• Could be other neurons, making them fire or, it could be effector cells, like muscles, that respond to this signal.