Module 2 Study Guide: Human Digestion, Absorption, Transport, and Carbohydrates

50 vocabulary flashcards reviewing human digestion, GI anatomy, accessory organs, microbiota, and carbohydrate classification and metabolism.

Mouth

The organ of the digestive system where mechanical breakdown and chemical digestion of carbohydrates begin, influenced by smell and taste.

Esophagus

The muscular tube that propels swallowed food from the mouth to the stomach.

Stomach

A digestive organ lined with gastric glands that secrete acidic gastric juice to carry out mechanical and chemical digestion.

Small Intestine

The digestive tract organ divided into three sections where the majority of nutrient breakdown and absorption takes place.

Large Intestine

The final section of the GI tract responsible for nutrient absorption, housing gut microbiota, and eliminating waste.

Pancreas

An accessory organ of digestion that produces essential digestive enzymes and hormones like insulin and glucagon.

Liver

An accessory digestive organ that processes absorbed nutrients, produces bile, and completes carbohydrate breakdown.

Gallbladder

An accessory organ that stores and concentrates bile produced by the liver before releasing it into the small intestine.

Sphincters

Muscular rings along the gastrointestinal tract that control the movement of food and prevent backflow between compartments.

Mechanical Digestion

The physical process of breaking down food and propelling it through the digestive tract through muscular activity.

Chemical Digestion

The enzymatic breakdown of food molecules into absorbable nutrient compounds.

Gut Microbiota

The community of microorganisms residing in the human digestive tract that plays key roles in digestion and overall health.

Probiotics

Live beneficial microorganisms consumed through fermented foods or supplements to promote a healthy gut microbiota.

Prebiotics

Nondigestible food fibers that feed and stimulate the growth of beneficial bacteria in the colon.

Fermented Foods

Food products created through controlled microbial growth that supply beneficial bacteria to support gut health.

Fecal Transplants

A medical procedure transferring stool from a healthy donor into a patient's colon to restore healthy gut microbiota balance.

Monosaccharides

The basic single-unit category of dietary carbohydrates, including glucose, fructose, and galactose.

Disaccharides

Carbohydrates composed of two monosaccharides linked together, including sucrose, lactose, and maltose.

Oligosaccharides

Complex carbohydrates containing 3 to 10 monosaccharide units bound together.

Starch

A digestible complex carbohydrate found in plant foods that supplies glucose for energy.

Glycogen

The human and animal storage form of glucose, primarily located in liver and muscle tissue.

Fiber

Nondigestible plant carbohydrates that pass into the colon, promoting healthy bacterial growth and bowel function.

Nutritive Sweeteners

Sweetening agents added to foods and drinks that provide energy and contribute calories.

Nonnutritive Sweeteners

FDA-approved high-intensity sugar substitutes that deliver sweet flavor with virtually no calories.

Soluble Fiber

Fiber that dissolves in water to form a gel-like substance, aiding in blood sugar control and cholesterol reduction.

Insoluble Fiber

Fiber that does not dissolve in water, increasing stool mass and facilitating transit through the digestive system.

Refined Carbohydrates

Processed carbohydrate foods that have had their dietary fiber, vitamins, and minerals removed during milling.

Insulin

A pancreatic hormone that lowers elevated blood sugar by promoting cellular glucose absorption and storage.

Glucagon

A pancreatic hormone that elevates low blood sugar levels by stimulating liver glycogen breakdown.

Ketone Bodies

Alternative energy molecules produced during fat breakdown when carbohydrate availability is extremely low.

Type 1 Diabetes

An autoimmune condition where the immune system destroys insulin-producing cells, requiring synthetic insulin treatment.

Type 2 Diabetes

A metabolic disorder characterized by cellular insulin resistance and relative insulin insufficiency.

Gestational Diabetes

A temporary form of high blood sugar developed during pregnancy due to hormonal impairment of insulin activity.

Hypoglycemia

A clinical condition marked by abnormally low blood glucose concentrations.

Hyperglycemia

A clinical condition marked by abnormally high blood glucose concentrations.

Metabolic Syndrome

A cluster of health indicators, including abdominal obesity and high blood pressure, increasing chronic disease risk.

Lactose Intolerance

An inability to digest lactose due to lactase enzyme deficiency, leading to gas, bloating, and distress.

High Fructose Corn Syrup (HFCS)

A manufactured nutritive corn sweetener containing fructose and glucose, commonly utilized in processed foods.

Sucrose

A disaccharide composed of equal parts glucose and fructose, commonly referred to as table sugar.

Glycemic Index

A scale ranking how rapidly carbohydrate-containing foods raise blood glucose levels compared to pure glucose.

Glycemic Load

A measurement that factors in both the glycemic index and total grams of carbohydrates in a standard serving.

Intestinal Villi

Finger-like fold projections on the wall of the small intestine that increase surface area for nutrient absorption.

Microvilli

Tiny microscopic projections on intestinal villi cells forming the brush border to absorb nutrients.

Gastric Juice

The fluid secreted in the stomach containing hydrochloric acid and enzymes to break down food.

Gastric Glands

Specialized tubular glands in the stomach wall that secrete gastric juice components.

Recommended Carbohydrate Intake Range

The DRI guideline establishing that $45-65\%$ of total daily calories should come from carbohydrates.

Low-Carbohydrate Diet Threshold

Diets supplying less than $10\%$ of total daily calories from carbohydrates, well below the recommended $45-65\%$ range.

DRI Added Sugars Intake Limit

The Dietary Reference Intakes guideline recommending a maximum intake of $32\,\text{g}$ of added sugars per day.

Caloric Value of DRI Added Sugar Limit

The total energy equivalent of the $32\,\text{g}$ added sugar recommendation, equal to $128\,\text{kcal}$.

Peristalsis

The continuous wave-like muscular contraction that propels food masses through the esophagus and GI tract.