BIOC33H3 Chapter Notes -Antigen Presentation, Regulatory T Cell, Stylopharyngeus Muscle
Document Summary
Objects that become stuck in the larynx or trachea are expelled by coughing. If the victim cannot breathe nor speak, the heimlich maneuver is used to help the victim. If the blockage remains, rescuers may perform a tracheostomy. In this procedure an incision is made through the anterior tracheal wall and a tube is inserted. Before deliver, pulmonary arterial resistance is high because the pulmonary vessels are collapsed. The rib cage is compressed, and the lungs and conducting passageways contain only small amounts of uid and no air. The rst inspired air enters the passageways with enough force to push the contained uids out of the way and in ate the entire broncheal tree and most of the alveoli. Surfactant covering the alveolar surfaces prevents their collpase. Mastication (chewing) breaks down tough connective tissues and plant bers and helps saturate the materials with salivary secretions and enzymes. The bulk of each tooth consists of a mineralized matrix similar to bone.
