Deglutition Flashcards
Stages of deglutition
- voluntary stage
- pharyngeal stage
- esophageal stage
- receptive relaxation of stomach
This initiates the deglutition process
Voluntary stage
How long do pharyngeal stage lasts?
It happens in less than two seconds
What happens in pharyngeal stage?
In pharyngeal stage:
trachea is closed,
esophagus is opened,
First peristaltic wzave pushes food into uppen esophagus
This receives sensory im0ulses from the mouth
Tractus solitarus
Where is tractus solitarus found?
Medulla oblongata
What is the swallowing center?
Medulla, lower pons
Where is food transported in esophageal stage?
Pharynx to stomach
Types of peristaltic movement in esophageal stage
Primary peristalsis
Secondary peristalsis
This is principally a reflex act
Pharyngeal stage
A continuation of initiated swallowing peristaltic wave
Primary peristalsis
How long does it take for food to pass i to the stomach during primary peristalsis?
8-10 secs
Upright: 5-8 secs
If food fails to move from esophagus to stomach during primary peristalsis, what will happen?
Secondary peristalsis takes place wherein the distension of esophagus will initiate it until all food are in the stomach.
A patient loss his vagal control due to brain paralysis, will the swallowing reflex be capable of performing peristalsis?
Yes, myenteric nervous system can still cause secondary peristalsis
How do pharyngeal stage aid in food transportation?
Pharynx to esophagus