. A text-book of animal physiology [microform] : with introductory chapters on general biology and a full treatment of reproduction, for students of human and comparative (veterinary) medicine and of general biology. Physiology, Comparative; Veterinary physiology; Physiologie comparée; Physiologie vétérinaire. 384 ANIMAL P : . iOLOOY. pharynx seize it and press it«' ^ '•.* vue gallot; when the mor- sel is small or liquid is ;.(red, it is rapidly propelled on- ward by the tongfue, the oesophagus and ^sharynx being largely passive at the time, though contracting slowly afterward; at the
. A text-book of animal physiology [microform] : with introductory chapters on general biology and a full treatment of reproduction, for students of human and comparative (veterinary) medicine and of general biology. Physiology, Comparative; Veterinary physiology; Physiologie comparée; Physiologie vétérinaire. 384 ANIMAL P : . iOLOOY. pharynx seize it and press it«' ^ '•.* vue gallot; when the mor- sel is small or liquid is ;.(red, it is rapidly propelled on- ward by the tongfue, the oesophagus and ^sharynx being largely passive at the time, though contracting slowly afterward; at the same time the larynx as a whole is raised, the epiglottis pressed down,' chiefly by the meeting of the tongue and itself, while its cushion lies oVer the rima gltMidis, which is closed or all but closed by the action of the sphincter muscles of the larynx, so that the food passes over and by this avenue of life, not only closed but covered by the glottic lid. The latter is not so essential as might be supposed, for persons in whom it was absent have been known to swallow fairly well. The ascent of the larynx any one may feel for himself; and the be- havior of the pharynx and larynx, especially the latter, may he viewed by the laryngoscope. The grip of the pharyngeal muscles and the oesophagus may be made clear by attaching a piece of food (meat) to a string and allowing it to be partially swallowed. The upward movement of food under the action of the con- strictors of the pharynx is anticipated by the closure of the passage by the palato-glossi of the anterior pillars of the fauces. The circular muscular fibers of the gullet are probably the most important in squeezing on the food by a peristaltic move- ment, passing progressively over the whole tube, though the longitudinal also take part in swallowing, perhaps, by steady- ing the organ. Swallowing will take place in an animal so long as the medulla oblongata remains intact; and the center seems to lie higher than that
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Keywords: ., bookauthormillswes, bookcentury1800, bookdecade1880, bookyear1889
