Physiology
Textbooks
Boundless Anatomy and Physiology
Digestive System
The Alimentary Canal
Physiology Textbooks Boundless Anatomy and Physiology Digestive System The Alimentary Canal
Physiology Textbooks Boundless Anatomy and Physiology Digestive System
Physiology Textbooks Boundless Anatomy and Physiology
Physiology Textbooks
Physiology
Concept Version 10
Created by Boundless

Esophagus

The esophagus is a muscular tube through which food passes from the pharynx via peristalsis to the stomach.

Learning Objective

  • Describe the role of the esophagus in digestion


Key Points

    • The esophagus is the muscular tube that moves food material from the pharynx to the stomach via waves of muscle movement known as peristalsis.The junction between the esophagus and the stomach is known as the gastroesophageal junction or GE junction.
    • The entry to the esophagus opens only when swallowing or vomiting, thanks to specialized muscles that control the opening movement.

Terms

  • peristalsis

    The rhythmic, wave-like contraction of both longitudinal and circular smooth muscle fibers within the digestive tract that forces food through it.

  • mucus

    A slippery secretion from the lining of the mucous membranes.

  • esophagus

    The esophagus is an organ in vertebrates which consists of a muscular tube through which food passes from the pharynx to the stomach.


Example

    • Swallowing is a voluntary act that utilizes the muscles of the mouth and tongue to push food into the esophagus. Once food material is pushed into the throat, or pharynx, the trachea (windpipe) is blocked by a flap of tissue known as the epiglottis, preventing aspiration of food. Food then moves down the esophageal tube through waves of muscle movement, or peristalsis, until it reaches the stomach. 

Full Text

The esophagus is an organ in vertebrates which consists of a muscular tube through which food passes from the pharynx to the stomach. It is a major component of the upper digestive system. The word esophagus is derived from the Latin œsophagus, which derives from the Greek word oisophagos, meaning "entrance for eating". It is lined with mucus to aid in the passage of food.

Esophagus

The location of the esophagus within the greater digestive system in humans.

Length and Location

In humans the esophagus is continuous with the laryngeal part of the pharynx within the neck, and it passes through the thorax diaphragm and into abdomen to reach the cardiac orifice of the stomach. It is usually about 10–50 cm long depending on individual height. Due to the inferior pharyngeal constrictor muscle, the entry to the esophagus opens only when swallowing or vomiting.

Layers of Tissue

The esophageal tube in humans is comprised of two main layers of smooth muscle, though striated muscle comprises the tube near the pharynx. This combination of muscle tissue allows peristalsis to push food downward, and aids in regurgitation at the pharynx. The innermost layer of smooth muscle is arranged in a series of concentric rings, while the outermost layer is arranged longitudinally.

In much of the gastrointestinal tract, smooth muscles contract in sequence to produce a peristaltic wave which forces a ball of food (called a bolus) from the pharynx to the stomach.

The Gastroesophageal Junction

The junction between the esophagus and the stomach (the gastroesophageal junction or GE junction) is not actually considered a valve in the anatomical sense, although it is sometimes called the cardiac sphincter. 

[ edit ]
Edit this content
Prev Concept
Pharynx
Mucosa
Next Concept
Subjects
  • Accounting
  • Algebra
  • Art History
  • Biology
  • Business
  • Calculus
  • Chemistry
  • Communications
  • Economics
  • Finance
  • Management
  • Marketing
  • Microbiology
  • Physics
  • Physiology
  • Political Science
  • Psychology
  • Sociology
  • Statistics
  • U.S. History
  • World History
  • Writing

Except where noted, content and user contributions on this site are licensed under CC BY-SA 4.0 with attribution required.