Pharynx/ Esophagus Flashcards
The pharynx is part of what two tracts?
GI & respiratory
What happens in the pharynx?
Food is directed into the esophagus through the act of (deglutition) swallowing
What 3 structures are found in the pharynx?
Epiglottis, eustachian tube, tonsils
What is the purpose of the epiglottis?
Laryngeal cartilage that covers the glottis during the act of swallowing - prevents food from being aspirated into the trachea
What is the purpose of the eustachian tube?
Helps equalize atmospheric pressure with the pressure in the middle ear
Where is the eustachian tube located?
Travels between the nasopharynx and middle ear
What are the purpose of the tonsils?
Protect against disease
What does the esophagus connect?
The pharynx to the stomach
The esophagus is a _____________ tube
Muscular
The esophagus is lined with _____________ ______________ that allows for expansion or dilation when food passes through
Folded mucosa
How many layers of muscle does the tunica muscularis consist of and what are they needed for?
2 - inner circular layer, outer longitudinal layer - needed to move food
What is prehension?
The process of bringing food into the mouth
What is the term for chewing?
Mastication
What system is salivary secretion regulated by?
Nervous system
Salivary secretion can also be triggered by ______________ responses
Conditioned - Learned responses in which salivation is initiated by association
What stimulation produces watery saliva?
Parasympathetic
What stimulation produces mucoid saliva?
Sympathetic
What is the term used for swallowing?
Deglutition
What are the 3 phases of deglutition?
- Voluntary
- Pharyngeal stage
- Esophageal stage
What is the pharyngeal stage of swallowing?
Involuntary - food bolus stimulates pressure receptors causing the pharynx to close and epiglottis to cover glottis. Wave of muscle contractions move across pharynx pushing food bolus into the esophagus
What is the esophageal stage of swallowing?
Involuntary - presence of food in the esophagus stimulates the swallowing center to initiate peristalsis
What is peristalsis?
Pattern of muscle contractions that propels food through the GI tract
What esophageal muscles are involved in peristalsis?
Circular muscle layer
