ANAT 025 Lecture Notes - Lecture 22: Pulmonary Pleurae, Respiratory Center, Carotid Sinus
Document Summary
Out in the visceral pleura, you have pressure receptors; and when lungs expand out to wall of rib cage, this puts pressure on lungs to depolarize the baroreceptors. Pneumotaxic center: inhibits the apneustic center to make expiration possible. Start out at rest: all cells are functioning normally and dumping carbon dioxide into the blood. Carbon dioxide concentration in the blood becomes high enough to depolarize chemoreceptors in aortic arch, carotid sinus, and hypothalamus. Those chemoreceptors send impulses to inhalation portion of rhythmicity center. The inhalation portion sends impulses to the diaphragm, which sends impulses to your external intercostals. The floor of the thoracic cavity lowers. The volume of the thoracic cavity, thus increases; you suck air in, and elevate your ribs. You suck in around 500 cc"s of air: this inflates lungs to push them out with enough pressure on the rib cage to fire pressure receptors in visceral pleura.
