Chapter 23 The digestive system: the mouth Flashcards
How many cavities does the mouth have?
2
What are the accessory organs of the mouth?
tongue, teeth, gums, salivary glands
What are the functions of the mouth?
ingestion, propulsion, mechanical digestion, chemical digestion
What is the oral cavity?
bordered by teeth and gums, hard and soft palate, oropharynx, tongue
What is the tongue maid of?
Mainly skeletal muscle. It is attached toe the oral cavity floor by the lingual frenulum (the stringy like thing under your tongue)
What are the digestive functions of the tongue?
propulsion - movement of material through the system; swallowing
Mechanical digestion - breaking food down into smaller pieces; chewing
What is the oral vestibule?
the second cavity in the mouth. It is bordered by teeth and gums/gingivae, inner lining of cheeks and lips; superior to labial frenulum and inferior labial frenulum pass through
What is the function of the teeth?
they function in mechanical breakdown/chewing
How many sets of teeth are there?
two; deciduous (milk teeth) and Permanent teeth
How many teeth are there in the deciduous/milk teeth
20 total; 8 incisors, 4 canines, 8 premolars, 12molars (3rd molars aka wisdom teeth)
How many permanent teeth are there?
32; 8 incisors, 4 canines, 8 premolars, 12 molars (3rd molars aka wisdom teeth
What is the general structure of a tooth?
It has 2 main regions; the crown and the root which meet at a minor neck region
What is the enamel of a tooth?
The white outer surface of the crown. It is the hardest substance in the body and is mainly composed of dense calcium salts
What is the dentin of a tooth?
yellowish, hard, bonelike material making up most of the tooth. It is the layer underneath the enamel
What is the cement/cementum of a tooth?
bony, outer surface of root; connects to periodontal ligament. It helps
What is the pulp of a tooth?
areolar connective tissue with blood vessels and nerves found in the pulp cavity and root canal
What are salivary glands?
glands that produce mucus/saliva
How many types of salivary glands are there?
there are 3 pairs; mucous and serous are the main secretory cells.
What are the largest salivary glands?
parotids; they are located deep to the skin and anterior to lower ear; the ducts open lateral to 2nd upper molar
What are submandibular glands?
medial to posterior mandible; duct opens into floor of oral cavity
what are sublingual glands?
located in floor of mouth; ducts open into floor of oral cavity
What is the pharynx?
it carries food from the mouth to the esophagus and air to the larynx.
How many parts of the pharynx are there?
2 general regions, the oropharynx and the laryngopharynx
What is the function of the pharynx?
propulsion, swallowing through action (peristalsis) of 3 skeletal muscles in pharyngeal wall.
What muscles are associated with the pharyngeal wall?
superior, middle, inferior pharyngeal constrictor muscles
What is the esophagus?
a muscular tube extending from laryngopharynx down posterior larynx, trachea, heart. It goes through the diaphragm to join stomach at cardiac sphincter.
How many layers does the wall of the esophagus have?
it has 4 general layers around lumen.
Mucosa
submucosa
muscularis externa
adventitia/serosa
What is the mucosa of the wall of the esophagus?
its the inner lining next to the lumen. it is stratified squamous epithelium similar to mouth and pharynx
What is the submucosa of the wall of the esophagus?
mainly areolar connective tissue with submucosal glands
What is the muscularis externa of the wall of the esophagus?
responsible for propulsion, swallowing function by peristalsis; inner circular layer and outer longitudinal layer of muscle; superior third is skeletal muscle; middle third is a mix of skeletal and smooth muscle; inferior third is smooth muscle
What is the adventitia/serosa of the wall of the esophagus?
mainly fibrous connective tissue which may connect to other structures
