STUDY GUIDE:  Lecture 18: Electrical communication - the nerve impulse
revised 05/05/2004 09:53 AM

General Readings:

Purves 6th edition (5th ed.)  [7th ed.]

  • Ch. 44 esp 785-792 (Ch. 41 esp 916-922) [Ch 44 esp 855-863] Synapses
Lecture: Major Topics

Action Potential, cont. -- Propagation

  • Generating an action potential -- ion currents/channels
  • Moving the message quickly down the neuron
    • increase diameter -- decrease axial resistance
    • myelination -- increase membrane resistance (decrease ion flow out)

Synaptic Transmission -- Moving the message on to the next cell

  • Presynaptic
    • neurotransmitters
    • release of neurotransmitters
  • Post-Synaptic
    • Receptors
    • EPSP, IPSP
  • Next Time -- wrap up of receptors, summation, organization of neurons into circuits & overall nervous system
More Detailed Readings in Texts

Both these texts give similar and detailed explanations, so it's a good idea to read one of them, but don't bother reading both:

  • Sherwood 5th edition [4th edition] 
    • Ch 4 -- 113-128 [103-119]  myelination & synapses
  • Becker 5th edition (4th ed)
  • 241-243 (248-251) myelination
  • 243-250 ( 251-259) synapses
Additional Outside reading:
Medical reference:
  • Multiple sclerosis and other diseases in which myelin degenerates, from the Merck Manual
Test yourself - The nuts and bolts
  • What are the advantages of having myelinated neurons?  If there are these advantages, why aren't all neurons myelinated?
  • What happens when the action potential reaches the pre-synaptic side of the axon terminal?
  • What happens on the post-synaptic side?  
  • Synapses are classified as inhibitory vs excitatory and direct vs. indirect. What are the features of each kind? Why are direct/indirect sometimes called fast/slow instead?
  • What are the common neurotransmitters?
Test yourself - Problem solving  Problem Set #8:  Questions 8-2 part D, 8-9 (except C), 8-10, 8-11, & 8-17.