Pharynx

Pharynx
Head and neck.
Pharynx
Gray's	subject #244 1141
Artery	ascending pharyngeal, ascending palatine, descending palatine
Vein	pharyngeal veins
Nerve	pharyngeal plexus
MeSH	Pharynx
Dorlands/Elsevier	p_16/12633198

The pharynx (plural: pharynges) is the part of the neck and throat situated immediately posterior to the mouth and nasal cavity, and cranial, or superior, to the esophagus, larynx, and trachea.

Functions

It is part of the digestive system and respiratory system of many organisms.

Because both food and air pass through the pharynx, a flap of connective tissue called the epiglottis closes over the trachea when food is swallowed to prevent choking or aspiration. In humans the pharynx is important in vocalization.

Parts

The human pharynx is conventionally divided into three sections:

Nasopharynx

The nasopharynx lies behind the nasal cavity.

Postero-superiorly this extends from the level of the junction of the hard and soft palates to the base of skull, laterally to include the fossa of Rosenmuller.

The inferior wall consists of the superior surface of the soft palate.

Oropharynx

The oropharynx lies behind the oral cavity.

• The anterior wall consists of the base of the tongue and the vallecula.
• The lateral wall is made up of the tonsil, tonsillar fossa, and tonsillar (faucial) pillars.
• The superior wall consists of the inferior surface of the soft palate and the uvula roughly at the level of C1.

Hypopharynx

The hypopharynx, also known as the laryngopharynx roughly corresponds to the levels between C3 to C6, it includes the pharyngo-oesophageal junction (postcricoid area), the piriform sinus, and the posterior pharyngeal wall.

Like the oropharynx above it the hypopharynx serves as a passageway for food and air and is lined with a stratified squamous epithelium.

It lies directly anterior to the upright epiglottis and extends to the larynx, where the respiratory and digestive pathways diverge.

At that point the laryngopharynx is continuous with the esophagus posteriorly. The esophagus conducts food and fluids to the stomach; air enters the larynx anteriorly. During swallowing, food has the "right of way", and air passage temporarily stops.

Additional images

Conducting passages.	Organs of the digestive system.	The entrance to the larynx, viewed from behind.
The position and relation of the esophagus in the cervical region and in the posterior mediastinum. Seen from behind.

Sagittal section of nose mouth, pharynx, and larynx.

References

• Stedman's/LWW 1551471
• Human Anatomy and Physiology Elaine N. Marieb and Katja Hoehn, Seventh Edition.
• TNM Classification of Malignant Tumours Sobin LH & Wittekind Ch (eds)Sixth edition UICC 2002 ISBN 0-471-22288-7

See also

• Adenoid
• Eustachian tube
• Hyoid
• Larynx
• Tonsil
• Uvula

External links

• SUNY Labs 31:st-1401

v • d • e Anatomy: respiratory system
Nose • Nasal cavity • Pharynx • Larynx • Trachea • Lungs • Bronchi • Alveoli • Conducting zone • Respiratory zone

v • d • e Anatomy of torso, digestive system: Gastrointestinal tract
Upper GI: to stomach	Mouth • Pharynx (nasopharynx, oropharynx, hypopharynx) • Esophagus • Crop
Upper GI: stomach	rugae - gastric pits - cardia/gland - fundus/gland - pylorus/gland - pyloric antrum - greater curvature - lesser curvature
Lower GI: intestines	Small intestine (duodenum, jejunum, ileum) • Vermiform appendix • Ileocecal valve - Large intestine: Cecum • Colon (ascending colon, hepatic flexure, transverse colon, splenic flexure, descending colon, sigmoid colon)
Lower GI: after intestines	Rectum (Houston valve, rectal ampulla, pectinate line) • Anal canal (anal valves, anal sinuses, anal columns) - Anus: Sphincter ani internus muscle • Sphincter ani externus muscle
Lower GI: continuous	GALT: Peyer's patches • M cells - intestinal villus • crypts of Lieberkühn • circular folds • taenia coli • haustra • epiploic appendix