SWALLOWING AND PERISTALSIS
SWALLOWING:
Movement of food from mouth through pharynx into esophagus and then the stomach
STEPS:
1.) A mass of chewed and moistened food (bolus) is pushed to back of mouth by tongue, in pharynx a swallowing reflex prevents food from entering lungs and directs it to the esophagus
2.) Muscle contractions in the esophagus (peristalsis) propel bolus
3.) Bolus passes through specific sphincter and goes into stomach (heartburn results from irritation of esophagus by leaking gastric juices from sphincter)
- Uvula- deflects large food particles (gag reflex)
- Soft palette- closes nasal cavity during swallowing
- Epiglottis- closes trachea during swallowing
PERISTALSIS:
- Rhythmic contractions of soft muscular esophagus lining, stomach and small intestine propels food through digestive tract
HERE IS A VIDEO OUTLINING THE STEPS IN DIGESTION:
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