Swallowing, or deglutition, moves food from the mouth to the stomach via the pharynx and esophagus. The process occurs in three stages: 1. In the mouth, food mixes with saliva and moves to the back of the tongue. The mouth closes, and the soft palate rises. 2. Food enters the pharynx, and respiration temporarily stops as the voice box rises. 3. Food passes into the esophagus, initiating rhythmic muscle contractions that push the food down. The esophageal sphincter relaxes, allowing food to enter the stomach. Swallowing is a largely involuntary reflex that requires saliva or a similar substance. Bodily position and food temperature also affect swallowing.

Why is swallowing important for our bodies?

Swallowing is vital because it moves food from your mouth through the pharynx and esophagus into the stomach, which is essential for digestion . This process involves several stages, beginning in the mouth where food mixes with saliva to ease its passage. Saliva also contains enzymes like amylase that start breaking down carbohydrates. Once the food reaches the pharynx, swallowing becomes involuntary, moving the food bolus towards the esophagus while temporarily inhibiting respiration. The esophageal sphincters then facilitate the entry of food into the stomach, preventing any backflow.

What are the main parts of the body involved in swallowing?

The pharynx, a cone-shaped passageway from the mouth and nose to the esophagus and larynx, is essential for swallowing. It has three divisions: the nasal, oral, and laryngeal pharynx. During swallowing, the tongue retracts, pushing food into the pharynx. The soft palate elevates to prevent food from entering the nasal pharynx. The larynx moves upward, and the epiglottis diverts food from entering the larynx. Pharyngeal constrictor muscles propel food down. The cricopharyngeal muscle relaxes, allowing food to enter the esophagus. Peristaltic contractions then move the food bolus toward the stomach.

How does the tongue help in the swallowing process?

The tongue is essential for swallowing, serving to knead food and mix it with saliva in the mouth. It manipulates food between the teeth for chewing and mixes it with saliva to moisten it. The tongue then forms the food into a rounded mass called a bolus. During swallowing, the tongue retracts and elevates to push the bolus into the pharynx. The tongue's muscles force the bolus from the mouth into the pharynx, initiating the involuntary swallowing process.

What are the different stages or phases of swallowing?

The act of swallowing, also known as deglutition, involves several coordinated stages that facilitate the safe and efficient passage of food from the mouth to the esophagus. Oral Phase The first stage is voluntary, where the bolus (a chewed mass of food) passes into the pharynx. The tongue retracts, mastication stops, and the back of the tongue elevates to push the bolus from the mouth into the pharynx. Pharyngeal Phase Entry of the bolus into the nasal pharynx is prevented by the elevation of the soft palate against the posterior pharyngeal wall. As the bolus is forced into the pharynx, the larynx moves upward and forward under the base of the tongue. The epiglottis diverts the bolus away from the larynx. The cricopharyngeal muscle relaxes, allowing food to enter the esophagus. Esophageal Phase The pharyngeal peristaltic contraction continues into the esophagus and becomes the primary esophageal peristaltic contraction.

How does the body prevent food from going into the windpipe during swallowing?

During swallowing, the body prevents food from entering the windpipe (trachea) through a coordinated process. When food is swallowed, the larynx moves upward, causing the epiglottis , a flaplike structure, to cover the entrance of the larynx. This action diverts the food bolus into the pharynx and then into the esophagus. The epiglottis protects the glottis during swallowing. The larynx then relaxes, returning to its normal position after the food passes into the esophagus.

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Also called:: Deglutition

Related Topics:: digestion; What Happens When You Swallow Gum?; How do snakes swallow large prey?; dysphagia

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Also known as: deglutition

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What is swallowing?
Swallowing, or deglutition, moves food from the mouth to the stomach via the pharynx and esophagus.

The process occurs in three stages:
1. In the mouth, food mixes with saliva and moves to the back of the tongue. The mouth closes, and the soft palate rises.
2. Food enters the pharynx, and respiration temporarily stops as the voice box rises.
3. Food passes into the esophagus, initiating rhythmic muscle contractions that push the food down. The esophageal sphincter relaxes, allowing food to enter the stomach.

Swallowing is a largely involuntary reflex that requires saliva or a similar substance. Bodily position and food temperature also affect swallowing.
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Why is swallowing important for our bodies?
Swallowing is vital because it moves food from your mouth through the pharynx and esophagus into the stomach, which is essential for digestion. This process involves several stages, beginning in the mouth where food mixes with saliva to ease its passage. Saliva also contains enzymes like amylase that start breaking down carbohydrates. Once the food reaches the pharynx, swallowing becomes involuntary, moving the food bolus towards the esophagus while temporarily inhibiting respiration. The esophageal sphincters then facilitate the entry of food into the stomach, preventing any backflow.
5 Britannica Sources
Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.
What are the main parts of the body involved in swallowing?
The pharynx, a cone-shaped passageway from the mouth and nose to the esophagus and larynx, is essential for swallowing. It has three divisions: the nasal, oral, and laryngeal pharynx.

During swallowing, the tongue retracts, pushing food into the pharynx. The soft palate elevates to prevent food from entering the nasal pharynx. The larynx moves upward, and the epiglottis diverts food from entering the larynx. Pharyngeal constrictor muscles propel food down. The cricopharyngeal muscle relaxes, allowing food to enter the esophagus. Peristaltic contractions then move the food bolus toward the stomach.
5 Britannica Sources
Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.
How does the tongue help in the swallowing process?
The tongue is essential for swallowing, serving to knead food and mix it with saliva in the mouth. It manipulates food between the teeth for chewing and mixes it with saliva to moisten it. The tongue then forms the food into a rounded mass called a bolus.

During swallowing, the tongue retracts and elevates to push the bolus into the pharynx. The tongue's muscles force the bolus from the mouth into the pharynx, initiating the involuntary swallowing process.
3 Britannica Sources
Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.
What are the different stages or phases of swallowing?
The act of swallowing, also known as deglutition, involves several coordinated stages that facilitate the safe and efficient passage of food from the mouth to the esophagus.
1. Oral Phase The first stage is voluntary, where the bolus (a chewed mass of food) passes into the pharynx. The tongue retracts, mastication stops, and the back of the tongue elevates to push the bolus from the mouth into the pharynx.
2. Pharyngeal Phase Entry of the bolus into the nasal pharynx is prevented by the elevation of the soft palate against the posterior pharyngeal wall. As the bolus is forced into the pharynx, the larynx moves upward and forward under the base of the tongue. The epiglottis diverts the bolus away from the larynx. The cricopharyngeal muscle relaxes, allowing food to enter the esophagus.
3. Esophageal Phase The pharyngeal peristaltic contraction continues into the esophagus and becomes the primary esophageal peristaltic contraction.
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1. human digestive system: Pharynx
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How does the body prevent food from going into the windpipe during swallowing?
During swallowing, the body prevents food from entering the windpipe (trachea) through a coordinated process. When food is swallowed, the larynx moves upward, causing the epiglottis, a flaplike structure, to cover the entrance of the larynx. This action diverts the food bolus into the pharynx and then into the esophagus. The epiglottis protects the glottis during swallowing. The larynx then relaxes, returning to its normal position after the food passes into the esophagus.
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Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

swallowing, the act of passing food from the mouth, by way of the pharynx (or throat) and esophagus, to the stomach. Three stages are involved in swallowing food.

The first begins in the mouth. There, food is mixed with saliva for lubrication and placed on the back of the tongue. The mouth closes, and the soft portion of the roof of the mouth (soft palate) rises so that the passageway between the nasal and oral cavities is closed off. The tongue rolls backward, propelling food into the oral pharynx, a chamber behind the mouth that functions to transport food and air.

Once food enters the pharynx, the second stage of swallowing begins. Respiration is temporarily inhibited as the larynx, or voice box, rises to close the glottis (the opening to the air passage). Pressure within the mouth and pharynx pushes food toward the esophagus. At the beginning of the esophagus there is a muscular constrictor, the upper esophageal sphincter, which relaxes and opens when food approaches. Food passes from the pharynx into the esophagus; the upper esophageal sphincter then immediately closes, preventing flow of food back into the mouth.

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Once food is in the esophagus, the final phase of swallowing begins. The larynx lowers, the glottis opens, and breathing resumes. From the time food leaves the mouth until it passes the upper sphincter, only about one second of time elapses, during which all these body mechanisms spontaneously occur. After passing the upper sphincter, movements in the esophagus carry food to the stomach. Rhythmic muscular contractions (peristaltic waves) and pressure within the esophagus push the food downward. Folds in the esophageal wall stretch out as materials pass by them and again contract once they have passed. At the lower end of the esophagus, the lower esophageal sphincter relaxes and food enters the stomach; the sphincter then closes again to prevent reflux of gastric juices and food materials.

Swallowing is basically an involuntary reflex; one cannot swallow unless there is saliva or some substance to be swallowed. Initially, food is voluntarily moved to the rear of the oral cavity, but once food reaches the back of the mouth, the reflex to swallow takes over and cannot be retracted.

Swallowing is influenced by bodily position. Liquids swallowed when the body is in an upright or horizontal position flow by gravity rapidly to the stomach; in the head-down position, however, liquids remain at the beginning of the esophagus and several swallows and peristaltic waves may be necessary to evacuate the liquid. If a person swallows food connected to a string with counterweights attached outside of the body, he can only overcome 5 to 10 grams of weight resistance. Dogs can swallow food with a resistance of 50 to 500 grams. Essentially, the swallowing capacity of human beings is much weaker than that of other animals. The temperature of foods also affects a person’s swallowing capacity. Very cold liquids (1° to 3° C, or 34° to 37° F) slow down or completely stop peristaltic movement in the esophagus. In contrast, liquids at high temperature (58°–61° C, or 136°–142° F) increase peristaltic movements.

Afflictions affecting swallowing include paralysis of the pharynx, failure of the esophageal sphincters to open properly, and spastic contractions of the esophageal muscle walls. Any of these may be caused by physical or psychological complications.

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