Digestive System Overview Quiz

Digestive System Overview

• Takes in food, breaks it down into nutrients, absorbs them into the bloodstream, and eliminates indigestible remains.

Gastrointestinal Tract

• Continuous muscular tube winding throughout the body, also known as the GI tract.

Accessory Digestive Organs

• Includes teeth, tongue, gallbladder, salivary glands, liver, and pancreas, aiding in digestion.

Segmentation

• A process that mixes food with digestive juices and enhances absorption by moving food over the intestinal wall.

Small Intestine Functionality

• The major organ for digestion and absorption of nutrients.

Ingestion Definition

• Food is contained in the gastrointestinal tract from ingestion until waste elimination.

Alimentary Canal

• Another term for the gastrointestinal tract.

Mouth Functions

• Ingestion: Voluntarily placing food in the oral cavity.
• Propulsion: Tongue initiates swallowing, moving food to the pharynx.
• Mechanical Digestion: Chewing and tongue movement.
• Chemical Digestion: Salivary amylase begins starch breakdown.

Pharynx and Esophagus

• Propel food bolus to the stomach via peristaltic waves, accomplishing involuntary swallowing.

Stomach Functions

• Mechanical Digestion: Food mixed with gastric juice and propelled into the duodenum via peristaltic waves.
• Chemical Digestion: Protein digestion initiated by pepsin.
• Absorption: Some fat-soluble substances, like aspirin and alcohol, are absorbed.

Small Intestine and Accessory Organs Functions

• Engages in mechanical digestion, propulsion, chemical digestion, and absorption.

Mesentery

• Structure that suspends the small intestine from the posterior body wall.

Villi

• Fingerlike extensions of the intestinal mucosa increasing surface area for absorption.

Peyer's Patches

• Large collections of lymphoid tissue located in the submucosa of the small intestine, contributing to immune function.

Circular Folds

• Deep folds of the mucosa and submucosa in the small intestine to enhance absorption.

Regions for Mechanical Breakdown

• Oral cavity and stomach are primarily responsible for mechanically breaking down food.

Tongue Function

• Mobile organ that manipulates food in the mouth and initiates swallowing.

Pharynx Role

• Serves as a conduit for both air and food.

Peritoneum Modifications

• Consists of greater omentum, lesser omentum, and mesentery, securing various digestive organs.

Esophagus

• Commonly referred to as the "gullet"; serves no digestive or absorptive function.

Rugae

• Folds of gastric mucosa that increase stomach surface area and contribute to digestion.

Haustra

• Sacculations of the large intestine, facilitating movement.

Microvilli

• Projections of the plasma membrane of mucosal epithelial cells, enhancing absorption.

Ileocecal Valve

• Valve at the junction of the small and large intestines controlling material passage.

Small Intestine as Absorption Site

• Primary area for food and water absorption, vital for nutrient uptake.

Frenulum

• Membrane securing the tongue to the floor of the mouth, aiding in food manipulation.

Large Intestine Functions

• Absorbs water and forms feces from indigestible materials.

Vestibule Definition

• Area between the teeth and lips/cheeks, contributing to oral cavity structure.

Appendix

• Wormlike sac that extends from the cecum, noted for potential immune functions.

Protein Digestion

• Initiated in the stomach, highlighting its critical role in breaking down proteins.

Lesser Omentum

• Structure attached to the lesser curvature of the stomach, part of the peritoneum.

Food Movement Control

• Pyloric valve regulates the transition of food from the stomach to the duodenum.