BIOL 3402 Lecture Notes - Lecture 2: Hemoglobin, Antiporter, Zymogen
Document Summary
Parasympathetic: stimulates digestion, fibers stimulate the glands to produce enzyme-rich saliva. Sympathetic: activity stimulates glands to produce less, thicker, mucusy saliva. Lower esophageal sphincter: prevents heart burn". Uses over 22 muscles in mouth, pharynx, and esophagus: swallowing center. 3 phases: oral phase: voluntary control. Food accumulates in oropharynx in front of epiglottis, tips food posterior and bolus slides around it and into laryngopharynx: pharyngeal phase: involuntary. Vocal lcords adduct to close airway: esophageal phase: involuntary peristalsis. Begins chemical digestion: chyme: soupy, semi-digested food in stomach. Most digestion after chyme passes to small intestine. Gastric secretions: gastric juice: 2-3 l. Hydrochloric acid: parietal cells produce hcl and contain carbonic anhydrase (cah, co2 and h2o h2co3 hco3 + h. Antiporter uses atp to pump h out and k in: hcl activates pepsin and lingual lipase, breaks up connective tissue and plant cell walls. Helps liquefy food to form chyme: converts ingested ferric ions (fe3) to ferrous ions (fe2)
