MCB 64
Final Exam
December 18, 2006

Limit each answer to half page. Return to by 11:00

  1. Action Potential: An axon is held at a potential that is just 5 mV negative from threshold, but depolarized enough that the action potential gates have begun to open. List all the channels through which ions are flowing, identify the ions, and their direction of flow. Be sure to describe both active and passive ionic pathways. What is the direction of net current through the membrane?

  2. Synapse: List all the channels through which ions flow, and identify their direction of flow in both the pre- and post-synaptic membranes of an ionotropic excitatory synapse. Start with the effect of depolarization at the presynaptic terminal, and end with the polarization of the postsynaptic membrane.

  3. Postsynaptic events: List the steps from the arrival of transmitter to activation of channels that take place at the classical cAMP metabotropic receptor.

  4. Olfaction: Describe the transduction process in olfaction. How does it differ from the classical second messenger pathway?

  5. Retina: A. Describe the sequence of neurons through which glutamate-carried excitatory information flows following photo transduction. Follow the signal from the photoreceptors to the optic nerve. B. Name the neurons through which inhibitory information flows.

  6. Cortex: Describe the visual cortical module. Indicate both layers and columns. Describe inputs and output layers. Characterize the different types of receptive fields at each layer.

  7. Audition: Describe all the channels that are modulated following shear of the inner hair cell cilia from auditory input to synaptic release.

  8. Muscle: Describe the contractile process within the sarcomere. Name the components. Indicate role of calcium.

  9. Invertebrate Memory: Describe the circuitry that underlies sensitization in Aplysia. Identify neurons, synaptic pathways, channels and transmitters.

  10. Vertebrate Memory: Describe the difference between LTP and LTD in the hippocampus. Identify transmitter(s), channels, ionic flow, intracellular mechanisms and structural changes.