Digestive

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small intestine

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the part of the intestine that lies between the stomach and colon, consists of duodenum, jejunum, and ileum, secretes digestive enzymes, and is the chief site of the absorption of digested nutrients

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pancreas

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a large lobulated gland that in humans lies in front of the upper lumbar vertebrae and behind the stomach and is somewhat hammer-shaped and firmly attached anteriorly to the curve of the duodenum with which it communicates through one or more pancreatic ducts and that consists of (1) tubular acini secreting digestive enzymes which pass to the intestine and function in the breakdown of proteins, fats, and carbohydrates; (2) modified acinar cells that form islets of Langerhans between the tubules and secrete the hormones insulin and glucagon; and (3) a firm connective-tissue capsule that extends supportive strands into the organ

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maltose

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malt sugar, is a disaccharide formed from two units of glucose joined with an α(1→4) linkage. It is the second member of an important biochemical series of glucose chains.

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maltase

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an enzyme that catalyzes the hydrolysis of maltose to glucose

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disaccharides

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any of a class of sugars (as sucrose) that on hydrolysis yields two monosaccharide molecules -- called also biose, double sugar

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trypsin

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a crystallizable proteolytic enzyme that differs from pepsin in several ways (as in being most active in a slightly alkaline medium and in hydrolyzing esters as well as amides) and that is produced and secreted in the pancreatic juice in the form of inactive trypsinogen and activated in the intestine

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chymotrypsin

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a protease that hydrolyzes peptide bonds and is formed in the intestine from chymotrypsinogen -

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carboxypeptidase

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an enzyme that hydrolyzes peptides and especially polypeptides by splitting off sequentially the amino acids at the end of the peptide chain which contain free carboxyl groups

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aminopeptidase

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an enzyme (as one found in the duodenum) that hydrolyzes peptides by acting on the peptide bond next to a terminal amino acid containing a free amino group

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dipeptidase

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any of various enzymes that hydrolyze dipeptides but not polypeptides

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Enterokinase

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an enzyme especially of the upper intestinal mucosa that activates trypsinogen by converting it to trypsin

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chyme

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the semifluid mass of partly digested food expelled by the stomach into the duodenum

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microvilli

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a microscopic projection of a tissue, cell, or cell organelle; especially : any of the fingerlike outward projections of some cell surfaces

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lactase

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an enzyme that hydrolyzes especially lactose to glucose and galactose and occurs especially in the intestines of young mammals and in yeasts

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amylase

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any of a group of enzymes (as amylopsin) that catalyze the hydrolysis of starch and glycogen or their intermediate hydrolysis products

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rectum

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the terminal part of the intestine from the sigmoid colon to the anus

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pancreatic amylase

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Amylase is produced in the pancreas and salivary glands and to a lesser extent the fallopian tubes. Very little is present in other organs. From the pancreas amylase is secreted via the pancreatic and then common bile ducts into the duodenum where it plays an important role in digestion of complex carbohydrates. In normal plasma about 40% of circulating amylase of pancreatic origin, the rest coming from the salivary glands.

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pharynx

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the part of the digestive and respiratory tracts situated between the cavity of the mouth and the esophagus and in humans being a conical musculomembranous tube about four and a half inches (11.43 centimeters) long that is continuous above with the mouth and nasal passages, communicates through the eustachian tubes with the ears, and extends downward past the opening into the larynx to the lower border of the cricoid cartilage where it is continuous with the esophagus

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epiglottis

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a thin lamella of yellow elastic cartilage that ordinarily projects upward behind the tongue and just in front of the glottis and that with the arytenoid cartilages serves to cover the glottis during the act of swallowing

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stomach

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a saclike expansion of the alimentary canal of a vertebrate communicating anteriorly with the esophagus and posteriorly with the duodenum and being typically a simple often curved sac with an outer serous coat, a strong complex muscular wall that contracts rhythmically, and a mucous lining membrane that contains gastric glands b : one of the compartments of a ruminant stomach <the abomasum is the fourth stomach of a ruminant>

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microvill

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structures that increase the surface area of cells by approximately 600 fold (human), thus facilitating absorption and secretion.

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lacteal

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relating to, consisting of, producing, or resembling milk

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alimentary canal

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the tubular passage that extends from mouth to anus, functions in digestion and absorption of food and elimination of residual waste, and includes the mouth, pharynx, esophagus, stomach, small intestine, and large intestine

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bile

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a yellow or greenish viscid alkaline fluid secreted by the liver and passed into the duodenum where it aids especially in the emulsification and absorption of fats

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enterogastrone

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a hormone that is held to be produced by the duodenal mucosa and to inhibit gastric motility and secretion

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maltase

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n enzyme that catalyzes the hydrolysis of maltose to glucose

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emulsification

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to disperse (as an oil) in an emulsion; also : to convert (two or more immiscible liquids) into an emulsion

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jejunum

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the section of the small intestine that comprises the first two fifths beyond the duodenum and that is larger, thicker-walled, and more vascular and has more circular folds and fewer Peyer's patches than the ileum

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peristalsis

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successive waves of involuntary contraction passing along the walls of a hollow muscular structure (as the esophagus or intestine) and forcing the contents onward

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enterogastrone

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a hormone that is held to be produced by the duodenal mucosa and to inhibit gastric motility and secretion

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lipase

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a water-soluble enzyme that catalyzes the hydrolysis of ester bonds in water–insoluble, lipid substrates. Lipases thus comprise a subclass of the esterases. Lipases are ubiquitous throughout living organisms, and genes encoding lipases are even present in certain viruses.

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salivary amylase

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both the salivary and pancreatic amylases are α-Amylases. both the salivary and pancreatic amylases are α-Amylases.

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feces

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bodily waste discharged through the anus

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cholecystokinin

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a hormone secreted especially by the duodenal mucosa that regulates the emptying of the gallbladder and secretion of enzymes by the pancreas and that has been found in the brain -- called also cholecystokinin-pancreozymin, pancreozymin

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large intestine (colon)

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he part of the large intestine that extends from the cecum to the rectum

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zymogens

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an inactive protein precursor of an enzyme secreted by living cells and converted (as by a kinase or an acid) into an active form -- called also proenzyme

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trypsin

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a crystallizable proteolytic enzyme that differs from pepsin in several ways (as in being most active in a slightly alkaline medium and in hydrolyzing esters as well as amides) and that is produced and secreted in the pancreatic juice in the form of inactive trypsinogen and activated in the intestine

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mucus

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a viscid slippery secretion that is usually rich in mucins and is produced by mucous membranes which it moistens and protects

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cecum

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a cavity open at one end (as the blind end of a duct); especially : the blind pouch at the beginning of the large intestine into which the ileum opens from one side and which is continuous with the colon

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goblet cells

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glandular simple columnar epithelial cells whose sole function is to secrete mucus.

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salivary glands

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in mammals are exocrine glands that produce saliva. In other taxa such as insects, salivary glands are often used to produce biologically important proteins such as silk or glues.

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liver

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a large very vascular glandular organ of vertebrates that secretes bile and causes important changes in many of the substances contained in the blood which passes through it (as by converting sugars into glycogen which it stores up until required and by forming urea), that in humans is the largest gland in the body, weighs from 40 to 60 ounces (1100 to 1700 grams), is a dark red color, and occupies the upper right portion of the abdominal cavity immediately below the diaphragm, that is divided by fissures into five lobes, and that receives blood both from the hepatic artery and the portal vein and returns it to the systemic circulation by the hepatic veins b : any of various large compound glands associated with the digestive tract of invertebrate animals and probably concerned with the secretion of digestive enzymes

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starch

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a white odorless tasteless granular or powdery complex carbohydrate (C6H10O5)x that is the chief storage form of carbohydrate in plants, is an important foodstuff, has demulcent and absorbent properties, and is used in pharmacy especially as a dusting powder and as a constituent of ointments and pastes

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cardiac sphincter

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the somewhat thickened muscular ring surrounding the opening between the esophagus and the stomach

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pyloric sphincter

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the circular fold of mucous membrane containing a ring of circularly disposed muscle fibers that closes the vertebrate pylorus -- called also pyloric valve

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saliva

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a slightly alkaline secretion of water, mucin, protein, salts, and often a starch-splitting enzyme (as ptyalin) that is secreted into the mouth by salivary glands, lubricates ingested food, and often begins the breakdown of starches

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pepsin

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a crystallizable protease that in an acid medium digests most proteins to polypeptides (as by dissolving coagulated egg albumin or causing casein to precipitate from skim milk), that is secreted by glands in the mucous membrane of the stomach of higher animals, and that in combination with dilute hydrochloric acid is the chief active principle of gastric juice

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appendix

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a bodily outgrowth or process

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secretin

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an intestinal proteinaceous hormone capable of stimulating secretion by the pancreas and liver

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gastrin

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any of various polypeptide hormones that are secreted by the gastric mucosa and induce secretion of gastric juice

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villi

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a small slender vascular process: as a : one of the minute fingerlike processes which more or less thickly cover and give a velvety appearance to the surface of the mucous membrane of the small intestine and serve in the absorption of nutriment and of which each has a central blindly ending lacteal surrounded by blood capillaries and covered with epithelium b : one of the branching processes of the surface of the chorion of the developing embryo of most mammals that are restricted to particular areas or diffusely arranged and over parts of the surface become vascular and help to form the placenta

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bile salts

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a dry mixture of the salts of the gall of the ox used as a liver stimulant and as a laxative -- called also ox bile extract, oxgall

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duodenum

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he first, shortest, and widest part of the small intestine that in humans is about 10 inches (25 centimeters) long and that extends from the pylorus to the undersurface of the liver where it descends for a variable distance and receives the bile and pancreatic ducts and then bends to the left and finally upward to join the jejunum near the second lumbar vertebra

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crypts

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an anatomical pit, depression, or invagination <a developing tooth in its bony crypt, such as the tonsillar crypt: any of the deep invaginations occurring on the surface of the palatine and pharyngeal tonsils.

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nucleases

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any of various enzymes that promote hydrolysis of nucleic acids

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sucrase

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enzymes that catalyse the hydrolysis of sucrose to fructose and glucose.

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ileum

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the last division of the small intestine that constitutes the part between the jejunum and large intestine and in humans forms the last three fifths of the part of the small intestine beyond the end of the duodenum and that is smaller and thinner-walled than the jejunum with fewer circular folds but more numerous Peyer's patches

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triglycerides

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any of a group of lipids that are esters formed from one molecule of glycerol and three molecules of one or more fatty acids, are widespread in adipose tissue, and commonly circulate in the blood in the form of lipoproteins -- called also neutral fat

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chylomicrons

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a lipoprotein rich in triglyceride and common in the blood during fat digestion and assimilation

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bolus

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a large dose of a substance given by injection for the purpose of rapidly achieving the needed therapeutic concentration in the bloodstream <the patient receives a bolus dose to reach the minimum effective analgesic concentration