. The eclectic guide to health; or, Physiology and hygiene ... ctimpressions to and from the nerve-cen-ters. The centers receive the impressionsbrought to them by the fibers, and sendout impulses along the fibers leading fromthem. The simplest possible arrangement ofnervous matter that can perform completenervous action must consist of one ormore cells acting as a center, with a fiberleading to it, and one leading from In the accompanying figure, c is thecenter, #, the fiber leading to it; bf thefiber leading from it. If now the fiber ais irritated at the end /, the irritation isconducted
. The eclectic guide to health; or, Physiology and hygiene ... ctimpressions to and from the nerve-cen-ters. The centers receive the impressionsbrought to them by the fibers, and sendout impulses along the fibers leading fromthem. The simplest possible arrangement ofnervous matter that can perform completenervous action must consist of one ormore cells acting as a center, with a fiberleading to it, and one leading from In the accompanying figure, c is thecenter, #, the fiber leading to it; bf thefiber leading from it. If now the fiber ais irritated at the end /, the irritation isconducted to the center c. An impulseis now sent along the fiber b to producemotion in the muscle m. You may illus-trate nervous action by your own feelingsand motions. If any thing touches yourfinger, the ends of the fibers in the fingerare irritated. This irritation is conveyedto your brain and you feel the touch,impulse from the brain along the fibers leading to themuscles, and thereby move your arm. In this way youexperience the complete action of nervous Fig. 49- Element of NervousSystem.—a. Sensory Motor fiber, c. End of sensory fiber, You now send an 112 PHYSIOLOGY. 113. The general nervous system consists of twosubdivisions : (1) That part which aids in thinking, feeling,and moving; and (2) that which is engaged in controllingthe vital organs. The first division is called the cerebro-spinal nervous system; the second is called the sympatheticnervous system.
Size: 874px × 2858px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, booksubjecthygiene, booksubjectphysiology, booky
