Introduction to Nutrition - Digestion & Absorption

These flashcards cover key terms and concepts related to the digestive system, digestion, and absorption processes, designed to aid in understanding and retention of the material.

Digestive System (plus body parts involved)

The system responsible for breaking down food and absorbing nutrients, consisting of the gastrointestinal tract and accessory organs. (GI tract (mouth, pharynx, esophagus, stomach, small intestine, large intestine, rectum, anus) and accessory organs (liver, pancreas, gallbladder, salivary glands)

Esophagus

The tube that connects the throat (pharynx) with the stomach, transporting food and liquids.

Chemical Digestion

The breakdown of large food molecules into smaller, absorbable molecules through enzymes.

Absorption

The process of taking up digested nutrients and water from the gastrointestinal tract into the bloodstream.

Peristalsis

Involuntary muscle contractions that move food along the digestive tract.

Chyme

The semi-liquid mixture of partially digested food and digestive juices in the stomach.

Plicae Circulares

Circular folds in the intestinal lining that increase the surface area for absorption.

Salivary Amylase

An enzyme in saliva that begins the breakdown of complex carbohydrates (starches) into simpler sugars like maltose in the mouth.

Intrinsic Factor

A protein secreted by the stomach linning necessary for the absorption of vitamin B12.

Villi

millions of tiny, finger-like projections lining the small intestine that drastically increase surface area to maximize nutrient absorption into the bloodstream

Gastrin

A hormone that stimulates the secretion of gastric acid (hydrochloric acid) in the stomach to aid digestion aids digestion by breaking down proteins and activating enzymes. 

Microvilli

Tiny projections on the surface of intestinal cells that further increase surface area for absorption. (on the surface of individual epithelial cells covering the villi.)

Bile

A digestive fluid produced by the liver, stored in the gallbladder, and released into the small intestine to aid in fat digestion (emulsify fats).

Proteolytic Enzymes

Enzymes that break down proteins into amino acids.

Mastication

The process of chewing food to break it down into smaller pieces.

Segmentation

A type of mechanical digestion in the small intestine that mixes food with digestive juices.

Gallbladder

An organ that stores and concentrates bile.

Pancreas

An organ that produces digestive enzymes and secretes buffers into the small intestine.

Large Intestine

The part of the digestive tract responsible for water reabsorption and the formation of feces.

Rectum

The final section of the large intestine that stores feces before elimination.

Accessory Organs

Organs that aid digestion but are not part of the gastrointestinal tract, including the liver, pancreas, gallbladder, and salivary glands.