Difference Between Pharynx and Larynx

Main Difference – Pharynx vs Larynx

Pharynx and larynx are two structures found in the neck region of vertebrates. The main difference between pharynx and larynx is that pharynx is a part of an alimentary canal, which extends from the nasal cavity and mouth to the larynx and the esophagus whereas larynx is the upper portion of the trachea. Both air and food pass through the pharynx. The air enters the larynx, and the food enters the esophagus. The wall of the larynx is made up of cartilage. The larynx is also called the vocal box since it contains vocal cords. The air passing through the larynx produces sound.

Key Areas Covered

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

Key Terms: Epiglottis, Esophagus, Larynx, Laryngopharynx, Mouth, Nasal Cavity, Nasopharynx, Oropharynx, Pharynx, Trachea, Vocal Cords, Vocalization, Vocal box

What is Pharynx

The pharynx is a region which is posterior to the oral and nasal cavities and the larynx. It has three regions: nasopharynx, oropharynx, and laryngopharynx. The nose opens to the nasopharynx through an opening called choana. A collection of lymphoid tissue called pharyngeal tonsils can be found in the nasopharynx. The auditory tube also opens to the nasopharynx. A fold of the mucous membrane called salpingopharyngeal fold accompanies the auditory tube. The oral cavity opens to the oropharynx. The base of the tongue is the floor of the oropharynx. The lateral walls of the oropharynx are formed by the palatoglossal and palatopharyngeal arches. The palatine tonsils occur between the two arches. The laryngopharynx is located behind the larynx. The wall of the laryngopharynx is made up of cartilage. The three regions of the pharynx are shown in figure 1.

Figure 1: Pharynx

The tonsillar artery along with the branches of the maxillary and the lingual arteries supply blood to the pharynx. The glossopharyngeal nerve, maxillary nerve, and the vagus nerve coordinate the functioning of the pharynx.

What is Larynx

The larynx is a hollow muscular organ which forms an air passage to the lungs and hosts the vocal cords. The larynx lies at the C4-6 vertebrae levels. The larynx is made up of cartilage, which is held together by ligaments and several membranes. The four cartilage that make up the larynx are thyroid cartilage, cricoid cartilage, arytenoid cartilage, and corniculate cartilage. The largest cartilage structure of the larynx is the thyroid cartilage. It is made up of two hyaline cartilage pieces. These two pieces meet from the front and the middle to produce the laryngeal prominence. The laryngeal prominence is also called Adam’s apple. The posterior portions of the two pieces form two horns called superior horn and the inferior hone. The only complete cartilage ring of the whole airway is the cricoid cartilage, which sits below the thyroid cartilage. The posterior part of the cricoid cartilage is taller than the anterior part. Two arytenoid cartilages sit on top of the posterior portion of the cricoid cartilage. The arytenoid cartilage is a small, pyramid-shaped cartilage. The two corniculate cartilages are connected to the arytenoid cartilages.

Both pharynx and the larynx are shown in figure 2.

Figure 2: Pharynx and Larynx

The epiglottis which occurs just behind the tongue is attached to the posterior portion of the thyroid cartilage. The Cricotracheal ligament, Median cricothyroid ligament, Thyrohyoid membrane, and the Quadrangular membrane connect each cartilage to form the structure of the larynx. The larynx consists of vocal cords, which are made up of a vocal ligament and vocalis muscles. The rima glottidis refers to the gap between the vocal cords. Since the larynx produces sounds with the aid of vocal cords, the larynx is called the vocal box.

Similarities Between Pharynx and Larynx

Both pharynx and larynx are components of the throat, which is located in the neck region.
Both pharynx and larynx pass the air.
Both pharynx and the larynx are involved in the swallowing.

Definition

Pharynx: Pharynx is a membrane-lined cavity behind the mouth and the nose, connecting them to the esophagus and the larynx respectively.

Larynx: Larynx is a hollow muscular organ, which forms an air passage to the lungs and hosts the vocal cords.

Location

Pharynx: The pharynx is located just behind the mouth.

Larynx: The larynx is located at the C3-6 vertebral levels.

System

Pharynx: Pharynx is a part respiratory system and digestive system.

Larynx: Larynx is a part of the respiratory system.

Walls

Pharynx: The walls of the pharynx are made up of muscles.

Larynx: The walls of the larynx are made up of cartilage.

Anatomy

Pharynx: The pharynx is made up of three regions; nasopharynx, oropharynx, and laryngopharynx.

Larynx: The larynx is made up of mainly four cartilage; thyroid cartilage, cricoid cartilage, arytenoid cartilage, and corniculate cartilage.

Structure

Pharynx: The pharynx is a set of regions.

Larynx: The larynx is an organ.

Vocal Cords

Pharynx: The pharynx does not consist of vocal cords.

Larynx: The larynx consists of vocal cords.

Conclusion

Pharynx and larynx are two components of the throat. The nasal and the oral cavities open into the pharynx. The pharynx opens into the larynx and the esophagus. The larynx opens into the trachea. Therefore, both food and air pass through the pharynx. The main difference between pharynx and larynx is the structure and the function of each component.

Reference:

1. “The Pharynx, Larynx, and Trachea.” Dummies,. Accessed 3 Oct. 2017.

Image Courtesy:

1. “Illu pharynx” By Arcadian – (Public Domain) via Commons Wikimedia
2. “Illu01 head neck” By Arcadian -(Public Domain) via Commons Wikimedia