Unit III - Neurophysiology
Name three main functions of nervous system.
Describe anatomical organization of nervous system (central and peripheral) and
its components.
Describe physiological organization of peripheral nervous system (afferent,
efferent). Explain the role of afferent division of PNS and compare its visceral
and somatic components. Explain the role of efferent division of PNS and
compare its autonomic (visceral) and somatic components. Name two branches
of autonomic nervous system and explain their roles in regulation of body
functions.
Describe the cellular components of a neuron (body, axon, dendrite, axon hillock
and synaptic knob).
Describe three types of neurons based on their structure, explain their function.
Give functional classification of neurons (motor, sensory and interneurons). Give
example using reflex arc.
Explain the following terms: electricity, voltage (potential difference), current,
resistance, polarity, electrical gradient, and chemical gradient.
Name different types of plasma membrane ion channels and explain how they
function; give examples. Compare intracellular and extracellular concentration of
sodium, potassium and chloride ions. Comment on the membrane permeability
for these ions at rest. Explain physiological bases for resting membrane potential.
What ion is mostly responsible for it? Is the resting membrane potential a truly
restful state or is it an active process? What is the role of sodium-potassium
pump in this process? What is the numerical value of resting membrane potential
in a neuron?
Define depolarization and hyperpolarization and explain how they are affected by
the change in the membrane permeability of different ions.
Explain how is the permeability of sodium and potassium voltage-gated channels
regulated. Describe three states of sodium voltage-gated channels.
Define action potential. Name the phases of action potential in a neuron. Explain
their ionic bases. Where action potential is normally generated? What is the role
of sodium-potassium pump in this process?
Explain the “All or None” principle. Give examples of subthreshold and threshold
impulses. Will the stronger stimulus case a larger action potential? How is the
strength of a stimulus transmitted in the nervous system?
Define absolute and relative refractory period. Explain the ionic bases for these
phenomena.
Define the terms insulator and conductor. Give examples.
Explain how the action potential is spreads along the axon, why does it normally
spread in only one direction, why it is said to be self-propagating and nondecremental?
Explain the structure and function of myelin. Compare the speed of conductance
in myelinated and unmyelinated axons. Explain physiological bases for saltatory
conduction.
Compare A, B and C fibers.
Explain what causes action potentials? Is it a spontaneous change or is it caused
by the change in the environment? Compare graded and action potential. Name
two types of graded potentials. BIO 231 Dr. Tanya McVay
Define receptors and classify them according to the type of energy to which they
respond. Describe how generator potentials are produced and explore their effects
on action potential production.
Compare phasic and tonic receptors. Define sensory adaptation.
Explain how different types of stimuli are conveyed to CNS: type of sensation,
place of origin of sensation and strength of stimulus.
Explain how the stimulus is passed from one neuron to the other. Compare
chemical and electrical synapses.
Identify the parts of the synapse. Explain the mechanism of synaptic transmission.
What is the role of calcium ion in this process? What is the role of
neurotransmitter?
Explain how is synaptic transmission terminated. What are the means by which
the neurotransmitter is removed from the synaptic cleft?
Explore the following neurotransmitters based on their chemical structure, place
of action, main effects on postsynaptic neurons: Acetylcholine, norepinephrine,
dopamine, serotonin, GABA, glutamate, glycine and endorphins. Name disorders
associated with their inadequate production.
Compare excitatory postsynaptic potentials and inhibitory postsynaptic potentials.
Name three types of synapses based on their location on a neuron.
Compare graded potentials (generator and postsynaptic) and action potentials.
Define neuronal pool and explain how neuronal recruitment relates to the strength
of the stimulus. Name four types of neuronal circuits. Explain the difference
between the serial and parallel processing.