PVS 2100 Lecture 10: resp system
14 Feb 2017
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Document Summary
Nasal cavity: nostrils (rostral end, right and left halves nasal septum medially, nasal turbinates (aka conchae, create turbulence to create peripheral pressure to throw. Nasopharynx/pharynx: 14 points to an opening (eustachian tube, 12=partial septum, guttural pouches, pouch-like extensions of tube in horses, swollen=young animals; guttural pouch tetany overdistended with air; prone to (fungal)infection, important in cooling of the brain, sinuses aren"t extensive enough. Surfactant: reduces surface tension, alveoli tend to collapse uid lines the alveoli, surfactant lowers the surface tension of this uid, produced from very late gestation onwards, premature birth respiratory distress due to inability to in ate lungs. Respiratory cycle: inspiration air intake, expansion of thorax, contraction of diaphragm, cranial and outward movement of ribs, expiration air out ow, muscles relax (elastic recoil in lungs, internal intercostals may contract during exercise, effect of negative intraplueral pressure on venous return.
