Body Basics: Chemistry, Physiology, and Digestion

Vocabulary flashcards reviewing essential concepts of general chemistry, human physiology, organ systems, and gastrointestinal digestion and absorption.

Chemistry

The study of the composition and characteristics of matter.

Human Physiology

The study of how the human body functions.

Elements

Substances that cannot be separated into simpler substances and serve as the building blocks of matter.

Solution

An evenly distributed mixture of two or more compounds.

Solvent

The primary component in a solution that dissolves the solute.

Solute

The lesser component in a solution that is dissolved in the solvent.

Solubility

A measure of how easily a substance (solute) dissolves in a liquid (solvent).

Acids

Chemical substances that donate hydrogen ions.

Bases

Chemical substances that accept hydrogen ions.

pH

A measure of the acidity or alkalinity of a solution.

Chemical Reaction

A process that changes the atomic arrangement of molecules.

Digestion

The process by which molecules in food are mechanically and chemically broken down.

Metabolism

The total of all chemical reactions occurring in living cells.

Organ

A collection of tissues that perform a specific function.

Organ System

A collection of organs that work together to perform a major function.

Gastrointestinal Tract

A continuous muscular tube extending from the mouth to the anus.

Bioavailability

The extent to which the digestive tract absorbs nutrients and how well the body uses them.

Mechanical Digestion

Physical processes such as biting and grinding actions that break and mash food into smaller pieces.

Chemical Digestion

The chemical breakdown of food involving saliva and digestive enzymes.

Taste Buds

Specialized sensory structures on the tongue and lining of the mouth and throat.

Five Basic Tastes

Sweet, sour, salty, bitter, and umami.

Enzyme

A protein that speeds up the rate of a chemical reaction without being altered during the process.

Esophagus

The muscular tube connecting the pharynx to the stomach.

Epiglottis

A flap of tissue that folds down over the trachea (windpipe) when swallowing.

Peristalsis

Muscular contractions that move small amounts of food and beverages through the intestinal tract.

Gastroesophageal Sphincter

A muscular ring at the end of the esophagus that controls the opening and closing of the stomach.

Chyme

A mixture of gastric juice and partially digested food produced in the stomach.

Mucus

A substance that lubricates and protects the stomach walls from damage by gastric fluids.

Pyloric Sphincter

A ring of muscle that controls the rate of chyme release into the small intestine.

Small Intestine

A 15-to-32-foot long portion of the GI tract where most nutrients are digested and absorbed.

Liver

An organ that processes and stores nutrients, manufactures cholesterol and bile, and filters and detoxifies blood.

Gallbladder

An accessory organ that stores bile to assist in fat digestion.

Pancreas

An organ that produces and secretes digestive enzymes and bicarbonate ions.

Villi

Tiny fingerlike projections lining the small intestine that expand its surface area for absorption.

Absorptive Cells

Cells on villi that remove nutrients from chyme and transfer them into intestinal blood or lymph vessels.

Large Intestine

An approximately 5-foot long organ containing the colon and rectum that absorbs water and minerals and forms feces.

Human Microbiome

A vast microbial community residing mostly in the colon that assists in immunity, chemical secretion, and nutrient breakdown.

Constipation

A digestive disorder characterized by difficult and infrequent bowel movements.

Diarrhea

A condition characterized by frequent, loose bowel movements.

Vomiting

The forceful contraction of abdominal muscles to expel toxic stomach and duodenal contents.

Heartburn

A gnawing pain or burning sensation in the upper chest caused by stomach acid backflowing into the esophagus.

Irritable Bowel Syndrome (IBS)

A condition characterized by intestinal cramps and abnormal bowel function ranging from diarrhea to constipation.