What is the Difference Between Esophagus and Throat

The main difference between esophagus and throat is that esophagus is between the pharynx and the stomach whereas throat is the front part of the neck, containing pharynx and larynx. Furthermore, food passes through the esophagus from the pharynx to the stomach while throat provides paths for the esophagus and trachea. 

The esophagus and throat are two organs found in the upper part of the digestive tract of vertebrates. Generally, they are pipe-like structures responsible for passing either food or air into the lower parts of the digestive or respiratory tracts, respectively. 

Key Areas Covered 

1. What is the Esophagus
     – Definition, Anatomy, Function
2. What is the Throat
     – Definition, Anatomy, Function
3. What are the Similarities Between Esophagus and Throat
     – Outline of Common Features
4. What is the Difference Between Esophagus and Throat
     – Comparison of Key Differences

Key Terms 

Digestive System, Epiglottis, Esophagus, Larynx, Pharynx, Throat, Trachea

What is Esophagus 

The esophagus is a muscular tube that belongs to the upper part of the digestive system of vertebrates. It also connects the throat to the stomach, conducting food and liquids swallowed into the pharynx in order to reach the stomach. Generally, the length of the esophagus is around 25 cm in adults. In addition to these, it occurs posterior to both the trachea and the heart. Usually, the esophagus passes through the esophageal hiatus in the diaphragm and reaches the stomach.

Figure 1: Esophagus

Furthermore, the upper esophageal sphincter is the structure responsible for closing the upper esophageal opening. During swallowing, it opens, allowing the food to move into the esophagus. Furthermore, peristalsis or the wave-like muscle contractions permits the movement of food through the esophagus. The lower esophageal sphincter prevents the backward movement of food in the stomach to the esophagus. However, vomiting voids the contents of the stomach through the esophagus. 

What is the Throat 

Throat is the front part of the neck of vertebrates. Generally, it occurs anterior to the vertebra. It consists of both pharynx and larynx. However, the most important anatomical structure found in the throat is the epiglottis, which is responsible for separating the pharynx from the larynx. It prevents the inhalation of food and drinks in the esophagus into the lungs. Therefore, the main function of the throat is to separate the pathways of the upper parts of both the digestive tract, which is the esophagus, and the respiratory system, which is the trachea. 

Pharynx 

The pharynx is a region posterior to the oral and nasal cavities and to the larynx. Basically, it has three regions: nasopharynx, oropharynx, and laryngopharynx. In general, the nose opens to the nasopharynx through an opening called choana. Also, a collection of lymphoid tissue called pharyngeal tonsils occurs in the nasopharynx while the auditory tube opens to the nasopharynx.

Figure 2: Pharynx and Epiglottis

On the other hand, the oral cavity opens to the oropharynx whose floor is the base of the tongue, while the laryngopharynx occurs behind the larynx. The wall of the laryngopharynx is made up of cartilage.  

Larynx 

The larynx is a hollow muscular organ, forming an air passage to the lungs while hosting the vocal cords. Typically, the larynx lies at the C4-6 vertebral levels. It is made up of cartilage held together by ligaments and several membranes. Normally, the four cartilages that make up the larynx are thyroid cartilage, cricoid cartilage, arytenoid cartilage, and corniculate cartilage. Among them, the largest cartilage structure is the thyroid cartilage made up of two hyaline cartilage. These two pieces meet from the front and the middle to produce the laryngeal prominence also called Adam’s apple.

Figure 3: Pharynx and Larynx

The posterior portions of the two pieces form two horns: superior horn and the inferior hone. The cricoid cartilage is the only complete cartilage ring of the whole airway, sitting below the thyroid cartilage. However, two arytenoid cartilages sit on top of the posterior portion of the cricoid cartilage. The arytenoid cartilage is small, pyramid-shaped cartilage. The two corniculate cartilages are connected to the arytenoid cartilages.  

Furthermore, cricotracheal ligament, median cricothyroid ligament, thyrohyoid membrane, and quadrangular membrane connect each cartilage to form the structure of the larynx. Moreover, larynx consists of vocal cords made up of a vocal ligament and vocalis muscles. Generally, the rima glottidis refers to the gap between the vocal cords. Since it produces sounds with the aid of vocal cords, the larynx is called the vocal box.   

Epiglottis 

The epiglottis is a leaf-shaped flap occurring behind the tongue, on top of the larynx. It is a hard, cartilaginous structure whose main function is to cover the trachea during swallowing. Therefore, it prevents food from entering the respiratory tract or aspiration.  

Moreover, the flap of the epiglottis is made up of elastic cartilage while a mucous membrane covers it. During breathing, it stands open, allowing the passage of air into the larynx. Furthermore, the epiglottis is used in some languages to produce epiglottal consonant speech sounds.  

Similarities Between Esophagus and Throat  

• Esophagus and throat are two pipe-like anatomical structures that occur in the upper part of the digestive system of vertebrates.  
• Both are responsible for passing either food or air to the lower parts of the digestive as well as the respiratory tract. 

Difference Between Esophagus and Throat 

Definition 

Esophagus refers to a part of the alimentary canal, which is a muscular tube lined with a mucous membrane, connecting the throat to the stomach, while throat refers to the part of the neck in front of the spinal column, serving as the passage to the stomach and lungs. 

Anatomy 

The esophagus is a muscular tube while the throat is mainly a cartilaginous structure. 

Occurrence 

Moreover, esophagus occurs between the pharynx and the stomach while the throat occurs in the front part of the neck. 

Anatomical Position 

The esophagus occurs posterior to both the trachea and the heart while the throat occurs anterior to the vertebra. 

Type of Organ System 

Furthermore, the esophagus belongs to the upper part of the digestive system while there are two components in the throat: pharynx, which belongs to the upper part of the digestive system, and the larynx, which starts from the pharynx and belongs to the upper part of the respiratory system. 

Function 

In addition, the esophagus allows passing food from the pharynx to the larynx while the throat is responsible for separating the pathways of food and air. 

Conclusion 

The esophagus is the muscular tube occurring between the pharynx and the stomach. Therefore, it belongs to the upper part of the digestive system and is responsible for passing food from the pharynx to the stomach by peristaltic contractions. In contrast, throat is an anatomical structure consisting of both pharynx and larynx. Moreover, the epiglottis is the main anatomical part of the throat, separating the esophagus from the trachea. Therefore, the throat commonly belongs to the upper parts of both digestive and respiratory systems. Hence, the main difference between esophagus and throat is their anatomy and function. 

References:

1. Ruiz, Atenodoro R., et al. “Throat and Esophagus – Digestive Disorders.” MSD Manual Consumer Version, MSD Manuals, Available Here.

Image Courtesy:

1. “2412 The Esophagus” By OpenStax College – Anatomy & Physiology, Connexions Web site. (CC BY 3.0) via Commons Wikimedia  
2. “Mouth and pharynx” By BruceBlaus. (CC BY 3.0) via Commons Wikimedia    
3. “Throat anatomy diagram” By Indolences – File:Throat Diagram.svg (CC BY-SA 3.0) via Commons Wikimedia