Digestive System Flashcards
Absorption
Is the processing of foods in absorbable form into the blood stream, most of which occurs in the small intestines.
Digestion
The process by which foods are broken down mechanically and chemically; then converted into absorbable forms or molecules small enough for blood to absorb.
Bile
Fluid secreted by the liver; stored, concentrated and released from the gall bladder into the duodenum.
Chyle
Contains lymph that is drained from the gastrointestinal tract.
Chyme
A mixture of partially digested food and gastric juice within the gastrointestinal tract.
Defecation
Discharge of feces from the rectum.
Deglutition
The act of swallowing.
Duodenum
First section of small intestine. Shaped like the letter C is the first foot or 10 inches of the small intestine. It lies near the head of the pancreas in a hollow surface. Common site for peptic ulcers.
Emulsify
To disperse (as an oil) in an emulsion. also : to convert (two or more immiscible liquids) into an emulsion .Mayo is a mixture or an emulsification of oil and water. Mustard helps to emulsify vinaigrette.
Esophagus
A portion of the gastrointestinal tract between the pharnyx and the stomach.
Hydrolysis
A chemical reaction in which water is used during the breakdown of complex molecules (i.e. carbohydrates, proteins, fats).
Ingestion
Introduction of food and drink into the GI tract.
Small Intestine
A convoluted (coiled) tube that extends from the stomach to the large intestine. The greatest amount of digestion takes place in the small intestine.
Peptic Ulcer
Are found in the mucous membranes of the esophagus, stomach or duodenum. These are areas where the tissue is destroyed, possible causes cigarette smoking, gastric acid/pepsin, stress, drugs/alcohol (aspirin).
Liver
An accessory organ of the digestive system. Main digestive function is to produce bile which emulsifies fat.
Mastication
The act of chewing.
Pancreas
An accessory organ that acts as a exocrine and endocrine gland. Produced pancreatic juice (exocrine) to help digest fats, proteins, carbohydrates and nucleic acids. Also produces hormones (endocrine), insulin and glycagon which regulate digestion of carbohydrates and blood sugar.
Peristalsis
Meaning to contract around- is the basic propulsive movement of the gastrointestinal tract.
Peritoneum
The area of the abdominal and pelvic cavities where the walls are lined with a serous membrane.
Saliva
Produced by the salivary glands, it is a clear fluid that acts as a buffer to fermentation acids that wear down teeth enamel, acts as a lubricant in chewing and swallowing and contains salivary amylase which converts starch into sugar (maltose).
Sphincter
A ring of muscle surrounding and serving to guard or close an opening or tube, such as the anus or the openings of the stomach.
Stomach
Located just below the diaphragm, the alimentary canal expands to form the stomach, a pouch-like structure that serves as a reservoir for food during the early stages of digestion.
Villi (villus-sligular)
Any of the fingerlike or threadlike projections from the surface of certain membranous structures, typically serving to increase surface area and facilitate the passage of fluid or nutrients.
Digestive Tube (alimentary canal)
Is a long muscular tube lined with mucous membranes, extending from the lips to the anus.
Accessory Organs
The function of the digestive tube or the alimentary canal are enhanced by the tongue, teeth, salivary glands, liver, gall bladder and pancreas.
Peritoneal Cavity
The space between the parietal and visceral layers of the peritoneum.
Peritoneal Fluid
The fluid that occupies the space between the parietal and visceral layers of the peritoneum.
Peritonitis
An inflammation of the peritoneum.
Buccal Cavity (mouth)
The oral cavity.
Crown
The part of a tooth above the gum line.
Root
The part of a tooth below the gum line. Roots are covered with cementum, a bone-like material.
Periodontal membrane
Connective tissue that connects the roots of teeth into the bone.
Enamel
Covers the crown of the tooth and is the hardest material in the body.
Dental caries
Is the result of the tooth enamel breaking down and the softer dentin of the tooth decaying.
Dentin
Calcified connective tissue, composes the bulk of the tooth.
Pulp chamber
Is the soft or pulpy connective tissue part of the tooth. It contains blood vessels and nerves.
Root canal
The canal which the blood vessels and nerves (branches of the trigeminal or fifth cranial nerve) enter the tooth.
Incisors
Are shaped like chisels and serve to cut (bite into) food.
Canines
Are shaped like a dog’s teeth and serve to tear and shred food.
Premolars
Are shaped with two pints or cusps and serve to crush and grind food.
Wisdom Teeth or Molars
Are the back teeth and they have several masses or round projections on the surface. They serve to crush and grind food.
Deciduous teeth
The primary teeth. Total number is 20.
(Incisors -2x4)+(Canine-1x4)+(Molar-2x4)=20
Permanent teeth
The secondary teeth. Total number is 32.
(Incisors -2x4)+(Canine-1x4)+(Pre-Molar-2x4)=(Molars-3x4)=32
Salivary gland
This accessory organ that consist of three pairs of salivary glands which pour their secretions into the mouth.
Parotid gland
This is the largest pair of salivary glands, lie below and in front of each ear.
Submandibular gland
A submaxillary salivary gland located under the tongue toward the inner surface of the mandible.
Sublingual gland
This salivary gland lies under the tongue anterior to the sub mandibular glands.
Peridontal disease
Occurs when dental carries slow down after age 35yo and occurs below the gum line. Plaque (tartar) is the major cause.
Plaque (tartar)
A mineral sediment from saliva that is the major cause of Peridontal disease.
Gingiva (gum)
Is a dense, fibrous tissue covered by mucous membrane that envelopes the alveolar processes of the upper/lower jaws and surrounds the neck of the teeth.
Gingivitis
An inflammation of the gums.
Pyorrhea
The purulent discharge from the gums.
Peridontitis
An inflammation of the Peridontium, involves the gum tissue and the supporting bone of teeth. Is the major cause of tooth loss after the age of 35yo.
Mumps
A viral infection of the salivary glands that can cause sterilization of males but can also be prevented by a vaccine.
Pharnyx (throat)
A funnel shaped muscular tube extending from the posterior nasal cavity to the esophagus and the Larnyx; composed of the Oropharynx and Nasopharnyx and the Laryngopharnyx.
Soft palate
The fleshy tissue located at the back of the mouth, which together with the hard palate forms the roof of the mouth.
Uvula
The fleshy body that hangs from the soft palate.
Epiglottis
The leaf-shaped cartiliage which covers the Larnyx during the swallowing.
Bolus
Chewed food mixed with saliva.
Esophagus (musculomembranous tube)
A collapsible musculomembranous tube located in the thoracic cavity that extends from the throat (Laryngopharnyx) to the stomach
Laryngopharnx
The lower portion of three divisions in the throat (gullet).
Stomach
Just below the diaphragm, the alimentary canal expands to form the stomach, a pouch-like structure that serves as a reservoir for food during the early stages of digestion.
Fundus
Lies above and to the left of the cardiac orifice, an opening so name because of its proximity to the heart.
Body of Stomach
The main and the largest portion.
Pylorus
The part of the stomach that is beyond the body and communicates with the small intestine (duodenum) by an opening surrounded by a muscular ring called the pyloric sphincter.
Lesser curvature
Is the shorter and medial border of the stomach.
Greater curvature
Is the longer (greater) lateral border.
Rugae
Wrinkles or folds that form in the mucous membrane when the stomach is empty. These wrinkles or folds disappears when the stomach fills.
Cardiac sphincter
Surrounds the opening between the esophagus and the stomach. Prevents the backflow of food into the esophagus
Pyloric sphincter
Surrounds the opening between the stomach and duodenum. Keeps food inside the stomach for 2-6 hours.
Chyme
A semi-liquid mixture of gastric juice and food.
Pepsin
An enzyme which initiates protein digestion. Water is the solvent. Hydrolysis is the reaction.
Mucin
Protects the stomach lining from being digested.
Intrinsic factor
Necessary for the absorption of vitamin B12 (extrinsic factor) and the prevention of pernicious anemia.
Hydrochloric Acid (HCl)
An acid that furnishes the proper pH for pepsin, helps absorption of iron, helps break down food fibers and destroys bacteria. Lowers pH.
Flatus
Is gas in the digestive tract that is passed through the anus.
Indigestion (dyspepsia)
Occurs most often due to excessive stress (anxiety) and emotional reaction. It occurs also as a result of organic disorders of the digestive tract or organs.
Heartburn
A common symptom of severe indigestion. Results from regurigation (backflow-vomit)
Gastritis
Is the inflammation of the stomach lining caused by medications, foods, alcohol and nicotine.
Adenocarcinoma
A type of cancer that starts in mucus-producing (glandular) cells. Many organs have these types of cells and adenocarcinoma can develop in any of these organs.
Jejunum
The second portion of the small intestine, extends from the duodenum to the ileum and is about 8 feet long.
Ileum
The third or last portion of the small intestine that is about 12-13 feet long (longest portion). It joins the large intestine at the level of the cecum (first part of the large intestine).
Large intestine (colon)
About 4.5-5 feet in length, 2.5 inches in diameter extends from the ileum to the anus. Has a larger role than the small intestine with a sacculated appearance (series of sacs)
Cecum
A blind pouch, 2-3 inches long, which hangs down at the junction of the ileum and the colon.
Ileocecal valve (or sphincter)
Lies between the ileum and the cecum and prevents the return of feces from the cecum into the small intestine.
Colonoscopy
Examination of the colon with a scope.
Vermiform appendix
Arises from the cecum about one inch below the ileocecal valve. Worm shaped (vermiform) and 4 inches long.
Ascending colon
Extends from the cecum to the undersurface of the liver where it turns to the left.
Transverse colon
Crosses the upper part of the abdominal cavity from the right to the left and turns downward.
Descending colon
Extends downward on the left side of the abdomen to the pelvis, where it turns towards the midline to become the sigmoid colon.
Sigmoid colon
Extends from the descending colon at the level of the pelvis to the rectum. The sigmoid is S-shaped as the name implies.
Rectum
Extends from the sigmoid colon to the anal canal and is about 5-6 inches long. Cancer may occur at any part of the colon, but it is more commonly found in the rectum.
Anal canal
Is the terminal portion of the large intestine. Extends from the rectum to the anus (opening to the outside of the body) and is about 1-1.5 inches long.
Anus
Opening to the outside of the body.
Intestinal Flora
The common inhabitants of the intestines of man and animals.
Enterobacteriaceae
A family of bacteria that are common inhabitants of the intestines in man and animals. Commonly known as enteric bacteria.
Putrifaction
The process of decay food into stool (feces).
Escherichia coli
A gram negative colon bacillus that is normally nonpathogenic in the intestinal tract. Outside the intestinal tract it can be responsible for infections like UTI.
Proteus vulgaris
An enteric bacilli that is normally found in the intestinal tract but also can be responsible for UTI’s outside the GI tract.
Indicator organisms
Are a group of bacteria such as E. coli and P. vulgaris that are gram negative bacilli. These organisms could indicate fecal contamination or be from fecal contamination.
Enteritis
Inflammation of the intestines.
Gastroenteritis
Inflammation of both the stomach and small intestine from virus’, bacteria, parasites or chemical agents.
Diarrhea
Frequent watery bowel movements that can result in dehydration or lack of absorption of nutrients.
Constipation
Hard stools or difficulty in defecation.
Diverticulitis
Weakness of the muscles of the colon (possibly caused by chronic constipation) that causes the formation of diverticula, small pouches found in the lining and wall of the colon. Inflammation may occur as bacteria or other irritating agents get trapped in these pouches.
Appendicitis
An inflammation of the appendix.
Appendectomy
The surgical removal of the appendix.
Peritonitis
An inflammation that is the result of the appendix rupturing and spreading infection within the peritoneum of the abdomen.
Hepatic artery
Supplies the liver with arterial blood.
Portal vein
Brings venous blood from the intestinal tract that is rich in nutrients to the liver for processing.
Hepatic vein
Carries venous blood from the liver to the inferior vena cava.
Jaundice (icterus)
A yellowed appearance of the skin and eye sclera.
Hepatitis
Inflammation of the liver.
Infectious hepatitis
Type A Hepatitis
Serum Hepatitis
Type B Hepatitis
Cirrhosis
Destruction of liver cells, which are replaced by necrotic or connective (scar) tissue. Impairs liver function and most commonly caused by alcohol.
Gall bladder
A muscular sac that stores and concentrates bile. Located on the inferior surface of the liver and shaped like a small pear, color can vary from yellow to brown to green.
Cholecystokinin
A hormone that is released from the duodenal mucosa in the presence of fat in the duodenum. This hormone then triggers the release of bile from the gall bladder to help digest fat.
Emulsification
The process where bile lowers the surface tension on large fat globules so they can be broken down into small molecules for enzymes (lipase) can act on them.
Lipase
An enzyme that breaks down fats in food so they can be absorbed in the intestines.
Protease
An enzyme that breaks down protein in foods so they can be absorbed in the intestines.
Cholelithiasis
Formation of gall stones.
Cholecystitis
Inflammation of the gall bladder.
Pancreas
A club-shaped organ, 6-9 inches long, located behind and under the stomach in the upper left quadrant of the abdomen under the ribs. Functions as an exocrine and endocrine gland.
Pancreatic juice
Secreted out of the pancreas (exocrine function) that contains digestive enzymes needed to digest fats, proteins, carbohydrates and nucleic acids.
Insulin
Call the antidiabetic hormone, that is essential for carbohydrate metabolism. Insulin is produced in the beta cells of the islets of Langerhans. Endocrine function, secreted within or inside of.
Glucagon
The glucose mobilizer that functions to raise the blood sugar. Glucagon produced in the alpha cells of the islets of Langerhans. Endocrine function, secreted within or inside of.
Islets of Langerhans
Part of the endocrine function of the Pancreas where hormones are produced.
Beta cells
The cells in the islets of Langerhans where insulin is produced.
Alpha cells
The cells in the islets of Langerhans where glucagon is produced.
Pancreatitis
Inflammation of the pancreas caused by the abnormal activation of its enzymes.
Salivary amylase
Initiates digestion- breaks down starches to sugar
