Anatomy and Physiology 241 Lecture Objectives The Nervous System & Brain
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Describe the general function of the nervous system. Explain the role of the nervous system in maintaining homeostasis.
Compare and contrast the nervous and the endocrine systems.
Describe the organization of the nervous system. Define CNS, PNS-afferent and efferent divisions, somatic nervous
system, automatic nervous system. Name the 2 divisions of the autonomic nervous system. What are where are ganglia
found?
Differentiate between neurons and neuroglia cells with respect to function. Identify the different types of neuroglia cellsastrocytes, oligodendrocytes, microglia, ependymal cells, satellite and Schwann cells. Be able to identify where they are
found in the nervous system and give their specific functions.
Describe the structure of a generalized neuron. Identify-cell body (soma), perikaryon, nucleus, nucleolus, centrioles,
axoplasm, axolemma, Nissl bodies, neurofibrils, nerve fibers, dendrite, axon, axon hillock, axon collateral, internode,
telodendria, synaptic terminal, node of Ranvier. Give function of each of these. Tell which cells myelinate axons in both
the PNS and the CNS. Describe the synapse in detail.
Define sensory neuron, motor neuron, interneuron and give the function and location of each. Know the difference,
location and function of preganglionic and postganglionic fibers and general number of each.
Be able to classify neurons as bipolar, unipolar and multipolar. Explain what this means. Give functions and locations.
Describe the potassium ion and sodium ion concentrations on either side of a resting neuron cell membrane. Explain
how these establish a membrane potential. Explain how sodium ions and potassium ions move across the cell
membrane and why different concentrations of these ions are found on opposite sides of a membrane-electrical forces,
chemical forces, channels. Tell what the net charge is-inside and outside a resting neuron cell membrane. Explain why
this difference in charges exists. How is the permeability of the cell membrane important in this? Why is resting potential
important in nerve conduction? Be sure you know how and why it is maintained. What does electrochemical gradient
mean? Know how it is maintained by the Na-K ATPase pump.
Describe the changes that happen to a neuron cell membrane when an appropriate stimulus is applied to it. Define local
potential and action potential and differentiate between the two. What does graded response mean? Describe what
happens when a local potential brings the membrane potential to threshold. What does threshold means? Define
depolarization, repolarization and hyperpolarization. Explain how membrane channels are important in this.
Describe the conduction of a nerve impulse along an unmyelinated and a myelinated axon. What does salutatory
conduction mean?
Give factors which affect the speed at which a nerve impulse travels along a nerve fiber. Give the types of nerve fibers
based on diameter. Define the “all or none” principle with respect to nerve impulses.
Give the steps of action potential generation and explain in detail what happens at each step. Be able to sketch one.
Define refractory period of a neuron. Give the difference between absolute and relative refractory periods. What happens
to nerve impulses with each type?
Explain the difference between electrical and chemical synapses and andrenergic and cholingergic, GABA-ergic. Explain
IPSP and EPSP. Be able to explain how an action potential is transferred from the presynaptic to the postsynaptic cell.
Give examples of different neurotransmitters and tell where each is used in the nervous system. Describe what happens
to neurotransmitters (concentrate on ACH) once they are released into the synaptic cleft.
Define summation. What is the difference between temporal and spatial summation? How are EPSPs and IPSPs
involved?
Describe single-series, divergence, parallel-circuit processing, convergence and reverberation circuits.