Digestion Flashcards
Intake of fluids or other substances by cells of the skin or mucous membranes; the passage of digested foods from the gastrointestinal tract into blood or lymph.
Absorption
A secretion of the liver consisting of water, bile salts, bile pigments, cholesterol, lecithin, and several ions; it emulsifies lipids prior to their digestion.
Bile
A soft, rounded mass, usually food, that is swallowed.
Bolus
The secreting cell of a gastric gland that produces pepsinogen, the precursor of the enzyme pepsin, and the enzyme gastric lipase. Cell in the parathyroid glands that secretes parathyroid hormone (PTH).
Chief cells
The semifluid mixture of partly digested food and digestive secretions found in the stomach and small intestine during digestion of a meal.
Chyme
The portion of the large intestine consisting of ascending, transverse, descending, and sigmoid portions.
Colon
The act of swallowing.
Deglutition
The mechanical and chemical breakdown of food to simple molecules that can be absorbed and used by body cells.
Digestion
The dispersion of large lipid globules into smaller, uniformly distributed particles in the presence of bile.
Emulsification
The part of the nervous system that is embedded in the submucosa and muscularis of the gastrointestinal (GI) tract; governs motility and secretions of the GI tract.
Enteric nervous system
A cell of the mucosa of the gastrointestinal tract that secretes a hormone that governs function of the GI tract.
Enteroendocrine cells
Glands in the mucosa of the stomach composed of cells that empty their secretions into narrow channels called gastric pits.
Gastric glands
A continuous tube running through the ventral body cavity extending from the mouth to the anus. Also called the alimentary (al?-i-MEN-tar-ē) canal.
Gastrointestinal tract
A liver cell.
Hepatocytes
A gland that opens onto the surface of the intestinal mucosa and secretes digestive enzymes. Also called a crypt of Lieberkühn (LĒ-ber-kūn).
Intestinal glands
One of many lymphatic vessels in villi of the intestines that absorb triglycerides and other lipids from digested food.
Lacteal
Chewing.
Mastication
Microscopic, fingerlike projections of the plasma membranes of cells that increase surface area for absorption, especially in the small intestine and proximal convoluted tubules of the kidneys.
Microvilli
A muscular layer (coat or tunic) of an organ.
Muscularis
A network of autonomic axons and postganglionic cell bodies located in the muscularis of the gastrointestinal tract.
Myenteric plexus
A type of secretory cell in gastric glands that produces hydrochloric acid and intrinsic factor.
Parietal Cells
One of the paired salivary glands located inferior and anterior to the ears and connected to the oral cavity via a duct (Stensen’s) that opens into the inside of the cheek opposite the maxillary (upper) second molar tooth.
Parotid glands
Protein-digesting enzyme secreted by chief cells of the stomach in the inactive form pepsinogen, which is converted to active pepsin by hydrochloric acid.
Pepsin
Successive muscular contractions along the wall of a hollow muscular structure.
Peristalsis
The largest serous membrane of the body that lines the abdominal cavity and covers the viscera within it.
Peritoneum
An enzyme in saliva that initiates the chemical breakdown of starch.
Salivary amalase
One of a pair of salivary glands situated in the floor of the mouth deep to the mucous membrane and to the side of the lingual frenulum, with a duct (Rivinus’) that opens into the floor of the mouth.
Sublingual glands
One of a pair of salivary glands found inferior to the base of the tongue deep to the mucous membrane in the posterior part of the floor of the mouth, posterior to the sublingual glands, with a duct (Wharton’s) situated to the side of the lingual frenulum.
Submandibular glands
A layer of connective tissue located deep to a mucous membrane, as in the gastrointestinal tract or the urinary bladder; the submucosa connects the mucosa to the muscularis layer.
Submucosa
A network of autonomic nerve fibers located in the superficial part of the submucous layer of the small intestine.
Submucosal plexus
A projection of the intestinal mucosal cells containing connective tissue, blood vessels, and a lymphatic vessel; functions in the absorption of the end products of digestion.
Villi
