Chapter 3: Organs of the Alimentary Canal Flashcards
When does digestion begin?
Digestion begins even before food enters your mouth.
What can stimulate the secretion of saliva?
The smell or sight of food that appeals to you can stimulate the secretion of saliva.
What glands are responsible for secreting saliva in the mouth?
The three pairs of large salivary glands—the sublingual, submandibular, and parotid glands—are responsible for secreting saliva in the mouth.
How much saliva does an adult secrete every day?
An adult secretes one to two liters of saliva every day.
What triggers salivation?
The thought or sight of food, especially if someone is hungry, can trigger salivation.
How many pairs of large salivary glands are there in the mouth?
There are three pairs of large salivary glands in the mouth.
What are the names of the three pairs of large salivary glands?
The three pairs of large salivary glands are the sublingual, submandibular, and parotid glands.
What is the role of the small salivary glands in the mouth and pharynx?
The small salivary glands in the mouth and pharynx contribute to saliva production, although the three pairs of large salivary glands secrete the majority of saliva.
How much saliva does an adult secrete every day?
An adult secretes one to two liters of saliva every day.
Which gland is responsible for secreting the majority of saliva in the mouth?
The sublingual, submandibular, and parotid glands collectively secrete the majority of saliva in the mouth.
What is the composition of saliva?
Saliva is 97% to 99.5% water.
What enzyme does saliva contain?
Saliva contains the enzyme amylase.
What is the role of amylase in saliva?
Amylase acts to break the bonds that link the components of carbohydrate molecules to each other.
What is formed when food is moistened by saliva and chewed?
When food is moistened by saliva and chewed, it forms a soft ball called a bolus.
How do the tongue and other mouth muscles contribute to the formation of a bolus?
The tongue and other mouth muscles shape and manipulate the moistened food into a bolus during chewing.
What structures are involved in the safety of swallowing?
The safety of swallowing depends on three structures: the soft palate, the epiglottis, and the larynx.
What does the soft palate do during swallowing?
The soft palate rises and closes off the nasal cavity during swallowing.
What is the role of the epiglottis during swallowing?
The epiglottis lowers to cover the entrance to the larynx, preventing food from entering the airway.
What happens to the larynx during swallowing?
The larynx rises during swallowing to help close off the entrance to the trachea.
What path does food take after swallowing?
After swallowing, food travels through the pharynx and enters the esophagus, which leads to the stomach.
Why is it important for the soft palate, epiglottis, and larynx to protect the trachea during swallowing?
Food caught in the trachea can block air from entering the lungs, potentially causing choking and death.
What can happen if food enters the trachea instead of the esophagus during swallowing?
Choking can occur, which can be life-threatening if not addressed promptly.
How can choking be prevented during swallowing?
The soft palate rises to close off the nasal cavity, the epiglottis lowers to cover the entrance to the larynx, and the larynx rises to close off the entrance to the trachea, ensuring that food enters the esophagus instead of the airway.
How many stages does deglutition (swallowing) occur in?
Deglutition occurs in three stages.
