Saliva, teeth, esophagus Flashcards
What does saliva contain?
Contains water (97%), enzymes, mucus, chloride, phosphate, bicarb ions
Why is saliva important?
Moisten mouth
Digest some starch (salivary amylase from parotid and sublingual glands)
Cleans teeth
Inhibits bacterial growth with lysozyme
Dissolve molecules to stimulate taste buds
What does saliva do?
IgA- immunoglobulin A
Enzymes- Salivary amylase, lysozyme
Water- Dissolves food for faster digestion
Mucus- to lubricate gland
Ion function- Chloride activates salivary amylase, phosphate and bicarb ions
Which nervous system keeps saliva flowing? Which causes drymout?
PNS- keeps saliva flowing
Sympathetic system- Dominates during stress, causes “dry mouth”
How does saliva “buffer” the mouth?
Monitors and maintains pH
When ______ enters the mouth, triggers saliva production
food
What happens to the salivary glands during nausea?
Will start salivating just before vomiting, to protect
How many baby teeth are there? What are they called?
20 primary teeth,
How many permanent teeth are there?
32 permanent teeth (including wisdom teeth)
Each tooth is in its own _______ held in place by ________ _________.
Alveolus
periodontal ligaments
What are insisors for?
designed for cutting
What are canines for?
Designed for tearing/piercing/shredding
What are molars for?
Designed for grinding/crushing
There are __ sets of premolars, which are also called ______.
2
Bicuspids
How many molars are there? What is the last one called?
3
Wisdom tooth
What is an impacted tooth?
Cannot erupt because blocked
When is enamel produced?
Before eruption
How thick is enamel? Is it replaceable?
About as thick as a dime
No
What is the hardest substance in the human body?
Enamel
What is dentin? What color is it?
A protein-rich bone-like material
Yellow-ish
_____ forms the bulk of a tooth
Dentin
When does dentin act as a “shock absorber”?
During chewing and biting
______ surrounds the pulp cavity.
Dentin
What is the pulp cavity? What does it contain?
A central cavity containing CT, blood vessels, and nerve fibers
What is the medical term for swallowing?
Deglutition
What are the three phases of deglutition?
Buccal phase
Pharyngeal phase
Esophageal phase
Which phase of deglutition is voluntary?
Only the buccal phase
During the buccal phase, a bolus of food pushed into the _________, the ______ ____ blocks the nasopharynx, the _______ blocks off the mouth and the _______ tips posteriorly to cover the opening to the larynx
oropharynx
soft palate
tongue
epiglottis
What happens in the pharyngeal phase of deglutition?
Draws the bolus into the esophagus
In the esophageal phase of deglutition, a wave of ________ takes bolus of food through the esophagus. The ______ muscles above bolus contract to push is down.
peristalsis
circular
In esophageal deglutition, ________ muscle below bolus widen as it contracts.
Longitudinal
Can you swallow upside down? How?
Yes. Due to peristalsis and the clsoing of longitudinal muscles.
After a meal, a little extra ______ is produced to clean the mouth.
saliva
What is the opening where esophagus pierces diaphragm?
Esophageal hiatus
Where does the esophagus join the stomach?
At the cardiac orofice
What 4 tunics does the esophagus have?
Tunica mucosa
Tunica submucosa
Tunica muscularis
Tunica adventitia
What epithelium is in the tunica muscosa of the esophagus?
Nonkeratinized stratified squamous
What is in the submucosal tunic of the esophagus?
CT, numerous mucus-producing glands, to lubricate food
What kind of muscles are in the tunica muscularis of the esophagus? How are they divided up?
Inner circular and outer longitudinal muscles
Superior ⅓ is skeletal muscle
Middle ⅓ is a mix of skeletal and smooth muscle
Inferior ⅓ is smooth muscle
What is the upper esophageal sphincter?
Circular muscle that relaxes during swallowing
What is the lower esophageal sphincter?
(LES sphincter)- Relaxes to allow food in, then closes (to prevent reflux)
What is GERD? And what is a common symptom?
Gastroesophageal refulx disease
Hearthburn
Anatomically, how does heartburn occur?
When LES sphincter doesn’t close, reflux or a “burning sensation is caused
Leads to acid destruction of lower esophagus
What is a peptic ulcer?
When HCl and pepsin erode the walls of the stomach, can also occur in esophagus and duodenum
