Module 3 - Digestive System Flashcards
What are the two main divisions of the digestive system?
1) The alimentary canal (AKA gastrointestinal tract)
2) The accessory organs
Describe the alimentary canal.
It is a continuous muscular tube starting at the mouth and ending at the anus. The parts are the mouth, pharynx, esophagus, stomach, small intestine, large intestine and anus.
What are the accessory digestive organs?
Teeth, tongue, salivary glands, pancreas, liver and gall bladder.
What does heterotrophic mean?
Heterotrophic means you must take in food and digest it- you cannot produce your own nutrients like plants do.
What is an omnivore?
An omnivore is an animal that eats both plants and animals.
Describe the structures of the mouth.
The opening of the oral cavity is the lips. The superior surface is the hard and soft palates. The inferior surface is the tongue. The posterior border of the superior surface is the uvula. The cheeks form the lateral borders.
What is the lingual frenulum?
The vertical mucous membrane that extends from the inferior surface of the tongue to the floor of the mouth.
What is mastication?
The process of chewing food.
What enzyme does saliva contain?
Amylase
The upper jaw is called the ______________.
The lower jaw is the _______________.
Maxilla
Mandible
Describe the structure of the tongue.
The tongue is a muscle that fills the mouth and moves food in the processes of chewing and swallowing. It attaches to the mandible and the hyoid bones. The superior surface is covered with 3 kinds of papillae: circumvallate, fungiform and filiform. Circumvallate and fungiform papillae both contain taste buds.
Where are taste buds located?
The wall of the mouth, surface of the oropharynx, and in the circumvallate and fungiform papillae of the tongue.
The pharynx is lined with two lavers of _________ that alternate to push food down the alimentary canal. The outer layer is ____________, and the inner layer is ______________.
Muscle
Circumferential, logitudinal.
What prevents food from entering the laynx?
The epiglottis.
The part of the alimentary canal that goes from the pharynx to the stomach is the ______________.
Esophagus
What are the four layers of the tissue that forms the esophagus through the large intestine?
1) Mucosa: secretes mucus into the interior of the gastrointestinal tract.
2) Submucosa :contains blood and lymph vessels, lymph nodes, nerves, and mucous glands.
3) Muscularis externa: two layers of muscle, the outer longitudinal fibers and inner circumferential fibers. The exception to this is the stomach, which has a third layer of muscle called the oblique layer.
4) Serosa: cells that make serous fluid.
What is the esophageal hiatus?
The esophageal hiatus is the hole in the diaphragm that the esophagus goes through.
Name the seven sphincters of the digestive tract.
The upper esophageal sphincter, The lower esophageal sphincter (a.k.a. cardiac sphincter or gastroesophageal sphincter), the pyloric sphincter, the sphincter of Oddi, the illeocecal sphincter, the inner anal sphincter and the external anal spincter.
What are the two curves in the stomach called?
The lesser curvature is the smaller interior curve, the greater curvature is the larger curve.

Define peristalsis.
The process of moving food along the alimentary canal via waves of muscular action.
Describe the peritoneum of the stomach.
The peritoneum stretched between the liver and the lesser curvature is called the lesser omentum. The peritoneum thatattaches to the greater curvature is called the greater omentum. It is a pocket of peritoneum tha hangs down over the small intestine and returns to the stomach. The transverse colon is inside the pocket. The greater omentum contains fat deposits and collections of macrophages.
What are the four regions of the stomach?
Cardiac
Fundus
Body
Pylorus
The folds of the stomach wall are called ______________.
Rugae
What is a gastric ulcer?
It is an open sore in the stomach, caused by Heliobacter Pylori, or by NSAID use.



























