Functions and Divisions of the Nervous System
1.List the basic functions of the nervous system.
2.Explain the structural and functional divisions of the nervous system. Histology of Nervous Tissue
3.List the types of neuroglia and cite their functions. 4.Define neuron, describe its important structural components, and relate each to a functional role. 5.Differentiate between a nerve and a tract, and between a nucleus and a ganglion. 6.Explain the importance of the myelin sheath and describe how it is formed in the central and peripheral nervous systems. 7.Classify neurons structurally and functionally.
8.Define resting membrane potential and describe its electrochemical basis. 9.Compare and contrast graded potentials and action potentials. 10.Explain how action potentials are generated and propagated along neurons. 11.Define absolute and relative refractory periods.
12.Define saltatory conduction and contrast it to conduction along unmyelinated fibers. The Synapse
13.Define synapse. Distinguish between electrical and chemical synapses by structure and by the way they transmit information. 14.Distinguish between excitatory and inhibitory postsynaptic potentials. 15.Describe how synaptic events are integrated and modified. Neurotransmitters and Their Receptors
16.Define neurotransmitter and name several classes of neurotransmitters. Basic Concepts of Neural Integration
17.Describe common patterns of neuronal organization and processing. 18.Distinguish between serial and parallel processing.
I.Functions and Divisions of the Nervous System (pp. 342–343; Figs. 11.1–11.2) A.The central nervous system consists of the brain and spinal cord, and is the integrating and command center of the nervous system (pp. 342–343; Figs. 11.1–11.2). B.The peripheral nervous system is outside the central nervous system (pp. 342–343; Fig. 11.2). 1.The sensory, or afferent, division of the peripheral nervous system carries impulses toward the central nervous system from sensory receptors located throughout the body. 2.The motor, or efferent, division of the peripheral nervous system carries impulses from the central nervous system to effector organs, which are muscles and glands. a.The somatic nervous system consists of somatic nerve fibers that conduct impulses from the CNS to skeletal muscles, and allow conscious control of motor activities. b.The autonomic nervous system is an involuntary system consisting of visceral motor nerve fibers that regulate the activity of smooth muscle, cardiac muscle, and glands.
II.Histology of Nervous Tissue (pp. 343–351; Figs. 11.3–11.5; Table 11.1) A.Neuroglia, or glial cells, are closely associated with neurons, providing a protective and supportive network (pp. 343–346; Fig. 11.3). 1.Astrocytes are glial cells of the CNS that regulate the chemical environment around neurons and exchange between neurons and capillaries. 2.Microglia are glial cells of the CNS that monitor health and perform defense functions for neurons. 3.Ependymal cells are glial cells of the CNS that line the central cavities of the brain and spinal cord and help circulate cerebrospinal fluid. 4.Oligodendrocytes are glial cells of the CNS that wrap around neuron fibers, forming myelin sheaths. 5.Satellite cells are glial cells of the PNS whose function is largely unknown. They are found surrounding neuron cell bodies within ganglia. 6.Schwann cells, or neurolemmocytes, are glial cells of the PNS that surround nerve fibers, forming the myelin sheath. B.Neurons are specialized cells that conduct messages in the form of electrical impulses throughout the body (pp. 346–351; Figs. 11.4–11.5; Table 11.1). 1.Neurons function optimally for a...