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This set of flashcards contains key vocabulary terms and definitions related to the organization and functions of the digestive system.

Oral Cavity

The site of ingestion and mechanical digestion with teeth and tongue.

Pharynx

Muscular propulsion of materials into the esophagus.

Esophagus

Transport of materials to the stomach.

Stomach

Chemical digestion of materials by acid and enzymes; mechanical digestion through muscular contractions.

Small Intestine

Enzymatic digestion and absorption of water, organic substrates, vitamins, and ions.

Large Intestine

Dehydration and compaction of indigestible materials in preparation for elimination.

Anus

The terminal end of the digestive tract where defecation occurs.

Teeth

Organs that perform mechanical digestion by chewing (mastication).

Tongue

Assists mechanical digestion with teeth and provides sensory analysis.

Salivary Glands

Secrete lubricating fluid containing enzymes that break down carbohydrates.

Liver

Secretes bile important for lipid digestion and performs many other vital functions.

Gallbladder

Stores and concentrates bile.

Pancreas

Produces digestive enzymes and hormonal secretions.

Digestion

The process of breaking down food into smaller components for absorption.

Motility

Movement of food through the digestive tract driven by muscle contractions.

Chemical Digestion

The breakdown of food through chemical processes involving enzymes.

Mechanical Digestion

The physical breakdown of food into smaller pieces to increase surface area for enzymes.

Peristalsis

Waves of muscle contractions that move bolus through the digestive tract.

Segmentation

Muscle contractions that mix digestive material with secretions without net forward movement.

Enzymatic Digestion

Digestion facilitated by enzymes that break down carbohydrates, proteins, and lipids.

Bile

A digestive fluid produced by the liver that emulsifies fats.

Chyme

Partially digested food, mixed with stomach secretions, that moves into the small intestine.

Villi

Finger-like projections in the small intestine that increase surface area for absorption.

Accessory Digestive Organs

Organs such as the liver, pancreas, and gallbladder that aid in digestion but are not part of the digestive tract.

Digestive Tract

The continuous tube from the mouth to the anus through which food passes.

Histology

The study of the microscopic structure of tissues.

Absorption

The process by which nutrients from the food are taken into the bloodstream.

Defecation

The elimination of feces from the digestive tract.

Mastication

The process of chewing food into small, digestible pieces.

Gingiva

Gums that surround the teeth.

Enamel

The hardest substance in the human body, covering the crowns of teeth.

Dentin

Layer that forms the bulk of a tooth, similar to bone without the cells.

Pulp Cavity

Interior chamber of a tooth that contains nerves and blood vessels.

Root Canal

The space within the root of a tooth that contains the pulp.

Cementum

Layer that covers the dentin of the root and anchors the periodontal ligaments.

Periodontal Ligament

Tissue that attaches the tooth to the jawbone.

Carbohydrases

Enzymes that break down carbohydrates.

Proteases

Enzymes that digest proteins into amino acids.

Lipases

Enzymes that digest lipids (fats).

Nucleases

Enzymes that digest nucleic acids into nucleotides.

Gastrin

A hormone that stimulates acid production in the stomach.

Secretin

A hormone that stimulates the pancreas to release bicarbonate to neutralize stomach acid.

Cholecystokinin (CCK)

A hormone that stimulates gallbladder contraction and bile release.

Vagus Nerve

The cranial nerve that innervates many organs in the digestive tract.

Hepatocyte

A liver cell involved in the metabolic processes of the liver.

Bile Salt Recycling

Bile salts are reabsorbed in the intestine and returned to the liver.

Microbiome

The collection of microorganisms living in and on the human body, especially in the gut.

Colonoscopy

A procedure to examine the large intestine for polyps or cancer.

Ileocecal Valve

The valve that prevents backflow from the large intestine to the ileum.

Haustra

Pouches in the colon that allow for expansion and contraction.

Omental Appendices

Small pouches of fat hanging off the colon.

Diverticulosis

A condition where small pouches form in the colon wall.

Constipation

Infrequent or difficult bowel movements.

Hemorrhoids

Swollen veins in the lower rectum and anus.

Peptic Ulcer

An open sore in the lining of the stomach or duodenum.

H. Pylori

A bacterium that can cause peptic ulcers.

Antacids

Medications that neutralize stomach acidity.

Enteroendocrine Cells

Cells in the gastrointestinal tract that secrete hormones.

Aging Effects on Digestion

Changes in the digestive system that may occur with age, including decreased motility and sensitivity.

Nutrient Absorption

The process of taking nutrients from food into the body's cells.

Feces Composition

Approximately 75% water and 25% solids including bacteria and indigestible material.

Anal Sphincters

Muscles controlling the release of feces; internal is involuntary and external is voluntary.

Lactose Intolerance

Inability to digest lactose, leading to gastrointestinal symptoms.

Cirrhosis

Scarring of the liver tissue.

Hepatitis

Inflammation of the liver.

Colonic Polyp

A growth on the lining of the colon that may become cancerous.

Flatus

Gas produced during digestion.

Bacterial Fermentation

The breakdown of undigested materials by bacteria in the large intestine.

Microscopic Anatomy of the Small Intestine

Includes villi, microvilli, and the brush border for enhanced absorption.