Define at least 10 terms relating to the digestive system.
Describe the four functions of the digestive system.
Identify at least 10 digestive system structures and the function of each.
Describe at lest five disorders of the digestive system.
Identify the location and function of three accessory organs of the digestive system.
Identify at least three methods of assessment of the digestive system.

Intro to HSTE Terms:
Alactasia - Malabsorpiton of lactose caused by a deficiency of the enzyme lactase.
Bile - Fluid that helps digest fat in the small intestine; produced by the liver and stored in the gallbladder.
Bolus - Rounded mass of food.
Bulimia - Excessive binge eating, which may be followed by self-induced vomiting or purging.
Cholecystectomy - Surgical removal of the gallbladder.
Chyme- Thick semiliquid contents of stomach during digestion.
Defecation - Evacuation of waste or fecal matter from rectum.
Deglutition- The act of swallowing.
Emesis - The act of vomiting, vomit.
Endoscopy- Visual inspection of a body cavity using a scope.
Enema - Liquid instilled into rectum.
Flatulence - Excessive air or gas in stomach or intestines leading to distention of organs.
Ingestion - Taking foods or medicine into the body through the mouth.
Jaundice - Yellow appearance resulting from bile pigment stored in the skin and sclera of the eyes.
Mastication- Process of chewing food.
Peristalsis - Wavelike series of contractions of the digestive system that propels the contents.
Sphincter- ringlike band of muscle that closes a passage or opening.
Villus - One of many tiny vascular projections on the surface of the small intestine

Medical Terminology Digestive System Terminology

Structure and Function of the Degestive System
The Digestive System contains organs that make up the alimentary canal, also known as the digestive tract which goes from the mouth to the anus. It is about 30 feet long. Unlike the other organs, it is not a sterile system because it is open at both ends. The main function of the system is called the gastrointestinal system which breaks down food to a form the body cells can use. The process includes transportation of food and wastes, physical and chemical breakdown, absorption of degested food, and final elimination of wastes. It aslp helps maintain the proper amount of water, electrolytes, and other nutrients in the body.

Organs of the Digestive Process
Your food enters the alimentary canal at the mouth. Our teeth bite and chew the food to break it down. The tongue is for tasting the food, chewing and swallowing. The hard palate is the anterior roof of the mouth. The soft palate tissue is not attached to bone on the posterior portion of the mouth like the hard palate. The uvula helps prevent food from entering the nasal cavity during swallowing. As we chew our food, it is mixed with our saliva. The three salivary glands secrete an enzyme that begins the chemical portion of the digestive process.

The Pharynx, or the throat, is divided into three portions called the nasopharynx, or the nose, the oropharynx, or the mouth, and the laryngopharynx, or our voice box. Food passes through the oropharynx from the mouth to the esophagus. The epiglottis is located at the junction of the esophagus and the oropharynx. The epglottis is a small piece of tissue that closes off the trachea to prevent food and moisture from entering the respiratory tract.

The esophagus is the tubelike structure that carries food from the mouth to the stomach. The bolus of food moves down the esophagus to the stomach with a slow, wavelike motion. Peristasis is a wave of contraction by which food is moved through the digestive system.

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(Stomach)external image image_stomach_large.jpg
In the stomach, the food bolus mixes with hydrochoric acid and the enzymes pepsin and gastrin to become chyme. The stoach is a calike muscular organ that churns and squeezes food and continues its physical breakdown. Digestion of protein begins in the stomach. A few substances, such as glucose, some drugs, and alcohol, are absorbed directly into the blood through the stomach walls. The cardiac sphincter is a valve that prevents the chyme from flowing back into the esoplagus. The pyloricsphincter vontrols the flow of the chyme into the intestines. It takes one to four hours for the stomach to empty the chyme into the intestines.

(Small Intestine)
From the stomach, the food enters the small intestine. The small intestine is longer and narrower than the large intestine. It is lined with tiny, threadlike projections of tissue called villi (singular, villus) that increase the are for absorption of nutrients. The three sections of the small intestine are the duodenum, the jejunum, and the ileum. The small intestine produces juices to aid the digestive process. Most absorption of digestive products occurs in the small intestine. When digestion is completed, carbohydrates have been reduced to sugar (monosacharide and discharide). Protein has been changed to amino acid and dipeptide. Fats have been reduced to fatty acid and glyceride.

(Large Intestine)
The large intestine has three major portions called the ascending colon, transverse colon, and descending colon. The appendix is a small tube of intestine descending from the side of the intestine with an unknown function in humans. Most of the water from ingested food is absorbed back into the blood through the walls of the large intesine, along with vitamins, electrolytes, and bile salts. The bacteria Escherichia coli normally resides in the large intestine and helps to form feces and to produce vitamin K. The feces, or waste materials, is collected in the rectum at the end of the large intestine and eliminated by defecation through the anus. Feces are composed of undigested food, bacteria, mucus, and water.

The peritoneum is a flat serous (moist) membrane that surrounds the abdominal vaity. It lubricates and prevents friction between the organs. The mesentery is a fan-shaped projection of peritoneum that contains blood vessels and nerves. It provides support and helps to keep the abdominal organs in place by binding to them.

Accessory Organs of the Digestive System
The digestive system has three accessory organs, which iad the process of food breakdown. These exocine, or ducted, organs carry digestive jiuces to the intestinal tract. The pancreas is the only organ with both exicrine and endocrine functions. The exocrine function of the pancreas is to excrete digestive enzymes into the small intestine. The enzymes include pancreatin, trypsin, maltase, amylase, and lipase. The liver is the largest gland in the body. It was many important functions in addition to producing bile to assist in the digestion of fat. The liver converts glucose to a storage form call glycogen. It stores the fat-soluble vitamins (A, D, E, and K) and vitamin B12. It also breaks down many of the toxins taken into the body, including alcohol. It destroys old red blood cells, reprocesses the products, and synthesizes blood proteins. The liver also produces choloesterol, coagulation prducts, and antibodies. The gallbladder, located adjacent to the liver, stores bile until it is needed in the small intestine for digestion of fatty food particles.

Assessment Techniques
Five types of assessment are commonly performed on the gastrointestinal system: radiography, endoscopy, gastricanalysis, fecal analysis, and palpation and auscultation.

Disorders of the Digestive System - Student Projects