L18 Ch25 Digestive System Study Review

What are the two main divisions of the digestive system?

Digestive Tract (Alimentary Canal) and Accessory Organs.

Which process is defined as the chemical breakdown of food into macromolecules?

Digestion.

What specific type of epithelium is found in the oral cavity, pharynx, and esophagus to provide protection against stress and abrasion?

Stratified Squamous.

Where in the digestive tract is simple columnar epithelium found for the purpose of secretion and absorption?

Stomach and small intestine.

Which layer of the digestive tract consists of areolar connective tissue with large blood vessels, lymphatics, and nerve fibers, and lies below the mucosa?

Submucosa.

What is the outermost layer of the pharynx, esophagus, and rectum?

Adventitia.

Which cells initiate contractions in the muscularis mucosae and muscular layer without neuronal stimulation?

Pacesetter cells.

What coordinated contraction moves a bolus in one direction through the digestive tract?

Peristalsis.

Which mesentery suspends most of the small intestine, specifically the jejunum and ileum?

Mesentery Proper.

What is the technical term for gums?

Gingiva.

What is the name of the hardest substance in the body, which covers the crown of a tooth?

Enamel (calcium phosphate crystals).

How many teeth are present in deciduous dentition versus permanent dentition?

Deciduous (Baby Teeth): $20$ teeth; Permanent (Adult Teeth): $32$ teeth.

What are the three phases of deglutition (swallowing)?

Buccal Phase, Pharyngeal Phase, and Esophageal Phase.

What are the three layers of smooth muscle found in the stomach's muscularis externa?

Oblique, Circular, and Longitudinal.

What are the mucosal folds in the stomach that allow for expansion called?

Rugae (Gastric Folds).

What are the three regions of the small intestine in order?

Duodenum, Jejunum, and Ileum.

Identify the three adaptations of the small intestine that increase surface area for absorption.

Plicae Circulares (Circular Folds), Villi, and Microvilli.

What longitudinal bands of smooth muscle in the large intestine create the haustra?

Teniae coli.

Which anal sphincter is composed of skeletal muscle and is under voluntary control?

External Anal Sphincter.

What structure is located at the corners of liver lobules and consists of an interlobular bile duct, a branch of the hepatic portal vein, and an interlobular artery?

Portal Triad.

Which cells in the pancreas are responsible for the exocrine function of secreting digestive enzymes?

Pancreatic Acinar Cells.

In the aging digestive system, what causes increased constipation?

Decreased smooth muscle tone leading to decreased motility.