What keeps food from going down your windpipe? | Reference.com What keeps food from going down your windpipe? A: Quick Answer When you swallow, a piece of cartilage called the epiglottis closes off the trachea, or windpipe, to prevent food from obstructing your airway, according to About.com. The epiglottis flap normally rests in a slightly upright position above the larynx, or voice box. The epiglottis temporarily folds over the larynx opening as food or beverages enter the throat, protecting the trachea and lungs, MedlinePlus states. Full Answer Food or small objects can accidentally enter the windpipe, especially if a person laughs or inhales while eating, according to HowStuffWorks. In most cases, food completely bypasses the respiratory system and continues down the digestive tract by entering the esophagus. A blocked airway may interfere with healthy breathing, causing symptoms ranging from wheezing and choking to loss of consciousness and permanent brain damage, says MedlinePlus. Parents are discouraged from giving babies and toddlers small toy pieces or foods because these objects can become choking hazards.

Physicians are often able to remove objects stuck in the trachea using medical instruments, but in urgent situations, they may need to insert a breathing tube or perform a tracheostomy by making a surgical incision in the neck. The epiglottis is not invulnerable. Prior to the widespread use of influenza vaccines, many young children suffered from bacterial infections in this area, according to About.com. A condition known as epiglottitis can cause uncomfortable inflammation, making it difficult to breathe and preventing the body from circulating oxygen. Anatomy of the Throat and Esophagus - Video & Lesson Transcript | Study.com Anatomy of the Throat and Esophagus Watch short & fun videos Start Your Free Trial Today An error occurred trying to load this video. Try refreshing the page, or contact customer support. You must create an account to continue watching Register for a free trial Are you a student or a teacher? I am a student Start Your Free Trial To Continue Watching As a member, you'll also get unlimited access to over lessons in math, English, science, history, and more. Plus, get practice tests, quizzes, and personalized coaching to help you succeed.

Coming up next: Anatomy and Physiology of the Stomach and Autonomic Nervous System Controls You're on a roll. Keep up the good work! Your next lesson will play in 10 seconds 0:06 Deglutition 1:16 Divisions of the Pharynx 3:05 Larynx and Epiglottis Add to Add to Add to Want to watch this again later? Log in or sign up to add this lesson to a Custom Course. Custom Courses are courses that you create from Study.com lessons. Use them just like other courses to track progress, access quizzes and exams, and share content. Teachers Organize and share selected lessons with your class. Make planning easier by creating your own custom course. Students Create a new course from any lesson page or your dashboard. From any lesson page: Click "Add to" located below the video player and follow the prompts to name your course and save your lesson. From your dashboard: Click on the "Custom Courses" tab, then click "Create course". Next, go to any lesson page and begin adding lessons. Edit your Custom Course directly from your dashboard. Personalize: Name your Custom Course and add an optional description or learning objective.

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We previously learned that the mouth breaks food down mechanically with the process of chewing. We also learned that food is broken down chemically in the mouth with the presence of enzymes in the saliva called salivary amylase. Once a bite of food is mixed with saliva and broken down by the teeth, it has been transformed into a slippery mass that can be easily swallowed. In this lesson, you will learn about the process of swallowing and the structures of the throat and the esophagus. To help understand this stage of digestion, let's visit with Frank. Frank recently finished a long day at work, and his stomach was growling. So, he stopped by the local hot dog stand for a quick bite to eat. Frank's teeth and saliva broke down his first bite of hot dog, and the slippery mass is now ready for deglutition. This is the term used to describe the act or process of swallowing. It will help you remember this term if you note that the root of the word comes from the Latin language and means to 'gulp or swallow.' Divisions of the Pharynx The three parts of the pharynx During deglutition, or swallowing, the partially digested food passes out of the mouth and into the pharynx .

The pharynx is what you might commonly refer to as your throat. Anatomically, it is described as the passage that leads from the cavities of the nose and the mouth to the rest of the alimentary canal. So we see that the pharynx is the upper part of the alimentary canal, which we previously learned is the name used to describe the continuous tube that travels through the body and allows for digestion and absorption of nutrients. An interesting point about the pharynx is that it not only carries the foods and drinks that you consume, it also carries air, which passes through on the way to the lungs. Now, you swallow hundreds of times a day and likely do not give the process much thought. However, there is a well-orchestrated series of events that must happen so that food and drink you swallow doesn't 'go down the wrong tube,' so to speak. So how does swallowing prevent food and drink from passing into the wrong tube? Well, to explain this, we need to take a closer look at the anatomy of the pharynx. We see that the pharynx has three divisions. The superior division is called the nasopharynx.

It's the part of the pharynx that is continuous with the nasal passages and nose. It's easy to remember this division because the word 'naso' means nose. The next division is the oropharynx. It's the part of the pharynx that lies at the back of the mouth. This division is also easy to remember because the word 'oro' means mouth. The lower division of the pharynx is called the laryngopharynx. It is the lower part of the pharynx that leads to the rest of the alimentary canal. You can recall this term by remembering that the word 'laryngo' means larynx. We will describe the larynx shortly. Larynx and Epiglottis Location of the larynx You can see from looking at the different divisions of the pharynx that food must be routed properly to make it down the alimentary canal. For example, if Frank's ability to swallow is compromised, his chewed-up hot dog could go out of his nose. But luckily for Frank, when he swallows, a flap called the soft palate works properly.

This is a soft flap of tissue at the roof of the mouth that closes the nasopharynx during swallowing. When Frank swallows his hot dog, the soft palate rises and directs the food mass down into the oropharynx. The next possible place that the food mass can get off track is if it were to pass into the larynx. The larynx is described as the air passageway to the lungs. Because the larynx contains the vocal cords, many people refer to it as the voice box. When Frank swallows his hot dog, the larynx rises, causing its opening to be covered by the flaplike epiglottis. The epiglottis is a flap of cartilage that guards the larynx during swallowing. So we see that during the act of swallowing, all undesired routes are blocked off. The tongue blocks the mouth, the soft palate closes off the passage to the nose and a flap called the epiglottis flops over the passage to the lungs. This is the well-orchestrated process of swallowing, and like we said earlier, you do this hundreds of times a day.

The process usually runs very smoothly, but you may have noticed that it doesn't always work so well, especially if you try to talk while swallowing. When you do this, it's possible to 'short-circuit' your routing mechanism. Because talking requires the larynx to be open, food can manage to enter the respiratory passage. This triggers a reflexive coughing, which forces air out of the lungs in an attempt to expel the food that went down the wrong tube. Once Frank's bite of hot dog enters his pharynx, the process of swallowing - and all digestion from this point on - is under reflexive control and no longer under his voluntary control. We previously learned that the parasympathetic nervous system is the division of the nervous system that is under involuntary control, and we see that the parasympathetic nervous system plays an important role in the digestion of food. Esophagus and Peristalsis Food is moved through the pharynx and then enters the esophagus. This is the muscular tube that connects the throat to the stomach. Your esophagus is about 10 inches long, and it acts only as a passageway for food and drink.

The esophagus passes behind the airway to the lungs and in front of the spinal column. It pierces the diaphragm before reaching the stomach. Esophageal muscles move in a wavelike pattern to transport food Food moves through your esophagus by a wavelike series of muscular contractions called peristalsis. The esophagus has two layers of muscles. There's a layer that runs up and down the esophagus in a longitudinal pattern, and a second layer that runs in circles around the tube-shaped organ. During peristalsis, the longitudinal muscles contract and then the circular muscles contract, pushing the food down toward the stomach. × Respiratory System Review - Anatomy with Walsh at Pope John Xxiii High School - StudyBlue list three functions of the respiratory system gas exchange between blood and external environment -exchange of gases (lungs in alveoli) -passageways to lungs- purify, warm and humidify incoming air what is another name for nostril? nare what is the nasal cavity divided by? nasal septum what function does the mucosa in the respiratory system provide -moistens air what is the purpose of the nasal conchae?

-increase surface area -increase air turbulence within the nasal cavity what is the epiglottis? a spoon- shaped flap of elastic cartilage that prevents food and water from going into the wrong tube what two parts of the respiratory system does the epiglottis divide? pharynx and larynx What functions does the larynx provide? -routes air and food into proper channels -plays a role in speech what prevents the trachea from collapsing? the c- shaped hyaline cartilage what is another name for the trachea? windpipe where is the apex of the lungs? near the clavicle (the superior portion) how many lobes does the right lung have? 3 how many lobes does the left lung have? 2 what is the pleural fluid? What is its purpose? it fills the are between the layers of pleura to allow guiding What is the actual site of gas exchange in the respiratory system? alveoli it coats gas-exposed alveolar surfaces how does gas enter and exit the respiratory system? diffusion compare the diaphragm and the inter coastal muscles in inspiration and expiration.

-inspiration: contract list some non respiratory air movement cough and sneeze, laughing, crying, yawning, hiccup describe the movement of gases in both systemic (internal) and pulmonary(external) circulation . pulmonary- CO2 diffuses out, O2 diffuses in systemic- CO2 diffuses in, O2 diffuses out once in the blood, how are CO2 and O2 transported? O2- attaches to hemoglobins in RBC's CO2- in plasma as bicarbonate ion, small amount on hemoglobin (separate from O2) what is the normal respiration rate? 12- 15 respirations per minute how does CO2 affect respiration rate? the more CO2, the more respiration.... changes act directly on the medulla oblongata effects of aging on the respiratory system -elasticity of lungs decreases Epiglottis | definition of epiglottis by Medical dictionary Epiglottis | definition of epiglottis by Medical dictionary epiglottis [ep″ĭ-glot´is] the lidlike cartilaginous structure overhanging the entrance to the larynx. adj., adj epiglot´tic.

The muscular action of swallowing closes the opening to the trachea by placing the larynx against the epiglottis. This prevents food and drink from entering the larynx and trachea, directing it instead into the esophagus. (See Plates.) Epiglottis in a sagittal section of the head and neck. From Dorland's, 2000. ep·i·glot·tis (ep'i-glot'is), [TA] A leaf-shaped plate of elastic fibrocartilage, covered with mucous membrane, at the root of the tongue, which serves as a diverter valve over the superior aperture of the larynx during the act of swallowing; it stands erect when liquids are being swallowed but is passively bent over the aperture by solid foods being swallowed. [G. epiglōttis, fr.

epi, on, + glōttis, the mouth of the windpipe] epiglottis /epi·glot·tis/ (-glot´is) the lidlike cartilaginous structure overhanging the entrance to the larynx, guarding it during swallowing.epiglot´tic epiglottis (ĕp′ĭ-glŏt′ĭs) n. pl. epi·glottises or epi·glottides (-glŏt′ĭ-dēz′) The thin elastic cartilaginous structure located at the root of the tongue that folds over the glottis to prevent food and liquid from entering the trachea during the act of swallowing. ep′i·glot′tal (-glŏt′l), ep′i·glot′tic (-glŏt′ĭk) adj. epiglottis [ep′iglot′is] Etymology: Gk, epi + glossa, tongue the thin, leaf-shaped cartilaginous structure that overhangs the larynx like a lid and prevents food from entering the larynx and the trachea while swallowing.

ep·i·glot·tis (ep'i-glot'is) [TA] A leaf-shaped plate of elastic cartilage, covered with mucous membrane, at the root of the tongue, which serves as a diverter valve over the superior aperture of the larynx during the act of swallowing; it stands erect when liquids are being swallowed but is passively bent over the aperture by solid foods that are being swallowed. [G. epiglōttis, fr. epi, on, + glōttis, the mouth of the windpipe] EPIGLOTTIS epiglottis (ĕp″ĭ-glŏt′ĭs) plural.epiglottides [Gr.] The uppermost cartilage of the larynx, located immediately posterior to the root of the tongue. It covers the entrance of the larynx when the individual swallows, thus preventing food or liquids from entering the airway.

epiglottidean (-glŏ-tĭd′ē-ăn), adjective See: illustration epiglottis A leaf-like cartilaginous structure, down behind the back of the tongue, which act as a kind of lid to cover the entrance to the voice-box (larynx) and prevent food or liquid entering it during the act of swallowing. Fig. 151 Epiglottis . The left-side cervical region in humans. epiglottis a thin flexible structure, made of CARTILAGE , with a leaf-like shape that guards the entrance to the larynx (the glottis) and prevents food material entering the TRACHEA during swallowing, when the larynx is moved upwards under the epiglottis. Epiglottis A leaf-like piece of cartilage extending upwards from the larynx, which can close like a lid over the trachea to prevent the airway from receiving any food or liquid being swallowed.

ep·i·glot·tis (ep'i-glot'is) [TA] A leaf-shaped plate of elastic cartilage, covered with mucous membrane, at the root of the tongue, which serves as a diverter valve over the superior aperture of the larynx during the act of swallowing; it stands erect when liquids are being swallowed but is passively bent over the aperture by solid foods that are being swallowed. [G. epiglōttis, fr. epi, on, + glōttis, the mouth of the windpipe] epiglottis (ep´iglot´is), n an elastic cartilage, covered by mucous membrane, that forms the superior part of the larynx and guards the glottis during swallowing. epiglottis the lidlike cartilaginous structure guarding the entrance to the larynx. The muscular action of swallowing closes the opening to the trachea by placing the larynx against the epiglottis. This prevents food and drink from entering the larynx and trachea, directing it instead into the esophagus. Respiratory System | Interactive Anatomy Guide Female Full Respiratory System Description [Continued from above] .

. . act as the functional units of the respiratory system by passing oxygen into the body and carbon dioxide out of the body. Finally, the muscles of respiration, including the diaphragm and intercostal muscles, work together to act as a pump, pushing air into and out of the lungs during breathing. Anatomy of the Respiratory System Nose and Nasal Cavity The nose and nasal cavity form the main external opening for the respiratory system and are the first section of the body’s airway—the respiratory tract through which air moves. The nose is a structure of the face made of cartilage, bone, muscle, and skin that supports and protects the anterior portion of the nasal cavity. The nasal cavity is a hollow space within the nose and skull that is lined with hairs and mucus membrane. The function of the nasal cavity is to warm, moisturize, and filter air entering the body before it reaches the lungs. Hairs and mucus lining the nasal cavity help to trap dust, mold, pollen and other environmental contaminants before they can reach the inner portions of the body. Air exiting the body through the nose returns moisture and heat to the nasal cavity before being exhaled into the environment.

Mouth The mouth, also known as the oral cavity , is the secondary external opening for the respiratory tract. Most normal breathing takes place through the nasal cavity, but the oral cavity can be used to supplement or replace the nasal cavity’s functions when needed. Because the pathway of air entering the body from the mouth is shorter than the pathway for air entering from the nose, the mouth does not warm and moisturize the air entering the lungs as well as the nose performs this function. The mouth also lacks the hairs and sticky mucus that filter air passing through the nasal cavity. The one advantage of breathing through the mouth is that its shorter distance and larger diameter allows more air to quickly enter the body. Pharynx The pharynx, also known as the throat, is a muscular funnel that extends from the posterior end of the nasal cavity to the superior end of the esophagus and larynx. The pharynx is divided into 3 regions: the nasopharynx, oropharynx, and laryngopharynx. The nasopharynx is the superior region of the pharynx found in the posterior of the nasal cavity.

Inhaled air from the nasal cavity passes into the nasopharynx and descends through the oropharynx, located in the posterior of the oral cavity. Air inhaled through the oral cavity enters the pharynx at the oropharynx . The inhaled air then descends into the laryngopharynx , where it is diverted into the opening of the larynx by the epiglottis. The epiglottis is a flap of elastic cartilage that acts as a switch between the trachea and the esophagus. Because the pharynx is also used to swallow food, the epiglottis ensures that air passes into the trachea by covering the opening to the esophagus. During the process of swallowing, the epiglottis moves to cover the trachea to ensure that food enters the esophagus and to prevent choking. Larynx The larynx , also known as the voice box, is a short section of the airway that connects the laryngopharynx and the trachea. The larynx is located in the anterior portion of the neck, just inferior to the hyoid bone and superior to the trachea.

Several cartilage structures make up the larynx and give it its structure. The epiglottis is one of the cartilage pieces of the larynx and serves as the cover of the larynx during swallowing. Inferior to the epiglottis is the thyroid cartilage , which is often referred to as the Adam’s apple as it is most commonly enlarged and visible in adult males. The thyroid holds open the anterior end of the larynx and protects the vocal folds. Inferior to the thyroid cartilage is the ring-shaped cricoid cartilage which holds the larynx open and supports its posterior end. In addition to cartilage, the larynx contains special structures known as vocal folds, which allow the body to produce the sounds of speech and singing. The vocal folds are folds of mucous membrane that vibrate to produce vocal sounds. The tension and vibration speed of the vocal folds can be changed to change the pitch that they produce. Trachea The trachea, or windpipe, is a 5-inch long tube made of C-shaped hyaline cartilage rings lined with pseudostratified ciliated columnar epithelium.

The trachea connects the larynx to the bronchi and allows air to pass through the neck and into the thorax. The rings of cartilage making up the trachea allow it to remain open to air at all times. The open end of the cartilage rings faces posteriorly toward the esophagus, allowing the esophagus to expand into the space occupied by the trachea to accommodate masses of food moving through the esophagus. The main function of the trachea is to provide a clear airway for air to enter and exit the lungs. In addition, the epithelium lining the trachea produces mucus that traps dust and other contaminants and prevents it from reaching the lungs. Cilia on the surface of the epithelial cells move the mucus superiorly toward the pharynx where it can be swallowed and digested in the gastrointestinal tract. Bronchi and Bronchioles At the inferior end of the trachea, the airway splits into left and right branches known as the primary bronchi. The left and right bronchi run into each lung before branching off into smaller secondary bronchi.

The secondary bronchi carry air into the lobes of the lungs—2 in the left lung and 3 in the right lung. The secondary bronchi in turn split into many smaller tertiary bronchi within each lobe. The tertiary bronchi split into many smaller bronchioles that spread throughout the lungs. Each bronchiole further splits into many smaller branches less than a millimeter in diameter called terminal bronchioles. Finally, the millions of tiny terminal bronchioles conduct air to the alveoli of the lungs. As the airway splits into the tree-like branches of the bronchi and bronchioles, the structure of the walls of the airway begins to change. The primary bronchi contain many C-shaped cartilage rings that firmly hold the airway open and give the bronchi a cross-sectional shape like a flattened circle or a letter D. As the bronchi branch into secondary and tertiary bronchi, the cartilage becomes more widely spaced and more smooth muscle and elastin protein is found in the walls. The bronchioles differ from the structure of the bronchi in that they do not contain any cartilage at all. The presence of smooth muscles and elastin allow the smaller bronchi and bronchioles to be more flexible and contractile.

The main function of the bronchi and bronchioles is to carry air from the trachea into the lungs. Smooth muscle tissue in their walls helps to regulate airflow into the lungs. When greater volumes of air are required by the body, such as during exercise, the smooth muscle relaxes to dilate the bronchi and bronchioles. The dilated airway provides less resistance to airflow and allows more air to pass into and out of the lungs. The smooth muscle fibers are able to contract during rest to prevent hyperventilation. The bronchi and bronchioles also use the mucus and cilia of their epithelial lining to trap and move dust and other contaminants away from the lungs. Lungs The lungs are a pair of large, spongy organs found in the thorax lateral to the heart and superior to the diaphragm. Each lung is surrounded by a pleural membrane that provides the lung with space to expand as well as a negative pressure space relative to the body’s exterior. The negative pressure allows the lungs to passively fill with air as they relax. The left and right lungs are slightly different in size and shape due to the heart pointing to the left side of the body.

The left lung is therefore slightly smaller than the right lung and is made up of 2 lobes while the right lung has 3 lobes. The interior of the lungs is made up of spongy tissues containing many capillaries and around 30 million tiny sacs known as alveoli . The alveoli are cup-shaped structures found at the end of the terminal bronchioles and surrounded by capillaries. The alveoli are lined with thin simple squamous epithelium that allows air entering the alveoli to exchange its gases with the blood passing through the capillaries. Muscles of Respiration Surrounding the lungs are sets of muscles that are able to cause air to be inhaled or exhaled from the lungs. The principal muscle of respiration in the human body is the diaphragm, a thin sheet of skeletal muscle that forms the floor of the thorax. When the diaphragm contracts, it moves inferiorly a few inches into the abdominal cavity, expanding the space within the thoracic cavity and pulling air into the lungs. Relaxation of the diaphragm allows air to flow back out the lungs during exhalation.

Between the ribs are many small intercostal muscles that assist the diaphragm with expanding and compressing the lungs. These muscles are divided into 2 groups: the internal intercostal muscles and the external intercostal muscles. The internal intercostal muscles are the deeper set of muscles and depress the ribs to compress the thoracic cavity and force air to be exhaled from the lungs. The external intercostals are found superficial to the internal intercostals and function to elevate the ribs, expanding the volume of the thoracic cavity and causing air to be inhaled into the lungs. Physiology of the Respiratory System Pulmonary Ventilation Pulmonary ventilation is the process of moving air into and out of the lungs to facilitate gas exchange. The respiratory system uses both a negative pressure system and the contraction of muscles to achieve pulmonary ventilation. The negative pressure system of the respiratory system involves the establishment of a negative pressure gradient between the alveoli and the external atmosphere. The pleural membrane seals the lungs and maintains the lungs at a pressure slightly below that of the atmosphere when the lungs are at rest. This results in air following the pressure gradient and passively filling the lungs at rest.

As the lungs fill with air, the pressure within the lungs rises until it matches the atmospheric pressure. At this point, more air can be inhaled by the contraction of the diaphragm and the external intercostal muscles, increasing the volume of the thorax and reducing the pressure of the lungs below that of the atmosphere again. To exhale air, the diaphragm and external intercostal muscles relax while the internal intercostal muscles contract to reduce the volume of the thorax and increase the pressure within the thoracic cavity. The pressure gradient is now reversed, resulting in the exhalation of air until the pressures inside the lungs and outside of the body are equal. At this point, the elastic nature of the lungs causes them to recoil back to their resting volume, restoring the negative pressure gradient present during inhalation. External Respiration External respiration is the exchange of gases between the air filling the alveoli and the blood in the capillaries surrounding the walls of the alveoli. Air entering the lungs from the atmosphere has a higher partial pressure of oxygen and a lower partial pressure of carbon dioxide than does the blood in the capillaries.

The difference in partial pressures causes the gases to diffuse passively along their pressure gradients from high to low pressure through the simple squamous epithelium lining of the alveoli. The net result of external respiration is the movement of oxygen from the air into the blood and the movement of carbon dioxide from the blood into the air. The oxygen can then be transported to the body’s tissues while carbon dioxide is released into the atmosphere during exhalation. Internal Respiration Internal respiration is the exchange of gases between the blood in capillaries and the tissues of the body. Capillary blood has a higher partial pressure of oxygen and a lower partial pressure of carbon dioxide than the tissues through which it passes. The difference in partial pressures leads to the diffusion of gases along their pressure gradients from high to low pressure through the endothelium lining of the capillaries. The net result of internal respiration is the diffusion of oxygen into the tissues and the diffusion of carbon dioxide into the blood. Transportation of Gases The 2 major respiratory gases, oxygen and carbon dioxide, are transported through the body in the blood. Blood plasma has the ability to transport some dissolved oxygen and carbon dioxide, but most of the gases transported in the blood are bonded to transport molecules.

Hemoglobin is an important transport molecule found in red blood cells that carries almost 99% of the oxygen in the blood. Hemoglobin can also carry a small amount of carbon dioxide from the tissues back to the lungs. However, the vast majority of carbon dioxide is carried in the plasma as bicarbonate ion. When the partial pressure of carbon dioxide is high in the tissues, the enzyme carbonic anhydrase catalyzes a reaction between carbon dioxide and water to form carbonic acid. Carbonic acid then dissociates into hydrogen ion and bicarbonate ion. When the partial pressure of carbon dioxide is low in the lungs, the reactions reverse and carbon dioxide is liberated into the lungs to be exhaled. Homeostatic Control of Respiration Under normal resting conditions, the body maintains a quiet breathing rate and depth called eupnea. Eupnea is maintained until the body’s demand for oxygen and production of carbon dioxide rises due to greater exertion. Autonomic chemoreceptors in the body monitor the partial pressures of oxygen and carbon dioxide in the blood and send signals to the respiratory center of the brain stem. The respiratory center then adjusts the rate and depth of breathing to return the blood to its normal levels of gas partial pressures.

Prepared by Tim Taylor, Anatomy and Physiology Instructor Epiglottis – Definition, Function, Location, Pictures and Problems Home > Human Anatomy > Epiglottis – Definition, Function, Location, Pictures and Problems Epiglottis – Definition, Function, Location, Pictures and Problems Page Contents 13 Epiglottis Pictures Ever wondered what keeps your food from going off into your windpipes while eating? It is the humble Epiglottis that does the job for you. Read and know all what is Epiglottis, its location, its function, the diseases that affect it and the treatment of those conditions. Epiglottis Definition Picture 1 – Epiglottis Source – daviddarling Epiglottis is structure of the body that hangs down the windpipe. When food is swallowed, the Epiglottis keeps it from entering the lungs. In the absence of Epiglottis a person can choke and cough every time while eating. Epiglottis Location Epiglottis is found at the entrance of the larynx. It projects sideways at the rear of the tongue and the hyoid bone .

Epiglottis Pronunciation = âA-pee-glot-tisâ. Epiglottis Action Normally, Epiglottis points upwards allowing free passage of air into the trachea and larynx. During eating and swallowing process, the Epiglottis shuts itself thus blocking the opening into the trachea. When the swallowing is done, the Epiglottis opens up again allowing normal breathing. Epiglottis and Swallowing The Epiglottis function in swallowing is a very important one. While swallowing food and water, it draws itself back to cover the entry point of the larynx which prevents food and drink from going into the windpipe. These edible substances enter the esophagus and directly go into the stomach. When the swallowing action ends, the epiglottis moves up once again making normal flow of air into the trachea (windpipe). Epiglottis Structure Epiglottis is composed of elastic cartilage. Cartilage is a tough elastic tissue. It is made of small bundles of fibers that are highly elastic. This makes it sturdy yet flexible.

The cartilage tissue in the Epiglottis is coated with mucus membranes. This makes it hard enough to form a barrier before the trachea while swallowing. At the same time, it is soft enough to fold itself once the action is done. Function of Epiglottis in the Respiratory System The Epiglottis function in respiratory system is a very important one. It is because of this cartilaginous structure that you do not choke while eating or drinking. It is because the Epiglottis shuts the entrance to the trachea that food and drinks are transferred to the digestive system. However, sometimes food or liquid falls into pockets at either side of the Epiglottis. These can be safely coughed up and choking can be prevented. This is the reason why it is not safe to talk while swallowing. How Does The Epiglottis Work? Most of us have no idea how the Epiglottis works inside our body. The function of the Epiglottis is highly interesting and important. As aforementioned, it is placed behind the hyoid bone in the neck.

During swallowing, the neck muscles lift the hyoid bone which causes the Epiglottis to fold down and obstruct the airway thus diverting the swallowed substances to the esophagus. Epiglottis and Glottis Many people tend to mistake the Epiglottis with the glottis. Both are structurally and functionally different parts of the anatomy. The epiglottis is the cartilage flap fixed to the entrance of the larynx. Glottis is the space lying between the vocal folds and arytenoid cartilages located in the larynx. In other words, it is an opening to the larynx. It is known as the organ of speech or the vocal equipment of the larynx. It is the Glottis where voice tone is produced. Epiglottis Function in Digestion Epiglottis automatically delivers food and nutrients to the digestive system. It is because of this organ that swallowed particles are diverted to the esophagus and not the respiratory system. While swallowing, the organ flops down to channelize the eaten particles directly to the stomach. Epiglottis Function in Speech The Epiglottis has a vital role in speech.

It acts as an articulator in the production of vowels and pharyngeal consonants. In pharyngeals, Epiglottis articulates against the posterior pharynx wall. During slow speech, the speech is generated through a narrow opening. While pronouncing vowels, the opening between the Epiglottis and the pharynx becomes larger. In case of pronunciation of consonants, the aperture becomes smaller. Epiglottis is also involved in whisper, though it is seen to be more retracted than in normal speech. Epiglottis Problems Like any other organ in the body, the Epiglottis can be affected by a number of conditions. Some of the main Epiglottis diseases are Epiglottitis This condition leads to the swelling of the Epiglottis. This inflammation is caused mainly by an infection due to Haemophilus influenza bacteria. However, it may also result from attack by other types of bacteria and viruses that can cause Upper Respiratory Infection. Epiglottitis bacterial infection is now a rare disease but was once one of the very common Epiglottis problems in children in the age group 2 to 6.

Today, it is rarely seen to affect adults. But it is a life-threatening disorder and can even lead to death due to breathing difficulties that it causes. Epiglottis Ulcers Ulcers in Epiglottis are highly discomforting. They can give rise to extremely uncomfortable symptoms like sore throat and blocked ears. The presence of ulcers in Epiglottis makes it very difficult to swallow food and water.Â The throat can pain even while swallowing your own saliva. Chlorhexadine, Phylorinol, Tetracycline and codeine can be effective in curing Epiglottis lesions. Epiglottis Surgery Some people inhale food particles into their lungs from the mouth. This problem is known as Chronic Aspiration and can cause frequent respiratory infections, coughs and sore throat. In such cases, the Epiglottis needs to be surgically modified. However, the aim of surgery is to only change the structure of the Epiglottis and not remove it altogether. Complete Epiglottis removal can cause serious problems. The air breathed in would enter the stomach and the food would travel to the trachea.

Epiglottis repair surgery intends to put an end to Chronic Aspiration without removing this vital organ. Epiglottis Pictures Want to check how the Epiglottis actually looks like? Here are some useful Epiglottis photos for you. Take a look at these Epiglottis diagrams and know about the appearance of this important anatomical organ. Picture 2 – Epiglottis Image Picture 3 – Epiglottis Photo Source – mycotopia Epiglottis is a very important part of our body. It is this organ that aids in speech and eating foods and drinks. It is also because of this body organ that proper respiration becomes possible for us. References: Basic Respiratory Anatomy and Physiology Basic Respiratory Anatomy and Physiology The human respiratory system consists of the nasal cavity, mouth, throat (pharynx), voice box (larynx), windpipe (trachea), bronchi, and lungs. Air is normally taken in through the mouth and nose. The nose is lined with a membrane (mucosa) that contain tiny hair-like projections called cilia.

To keep dust and foreign particles from reaching the lungs, the cilia trap them and sweep them out of the nose. Airstreams which enter through the nose and mouth meet in the back of the throat (the pharynx). Continuing downward, there are two passages, one for food and liquids (the esophagus) and the other for air (the trachea). Several mechanisms prevent food and liquid from going down the wrong passageway into the trachea (aspiration). The most important protective mechanism is the action of the vocal cords, which close over the trachea during swallowing to temporarily seal off the airway. The larynx also rises up in the neck during swallowing, which directs material towards the esophagus. Finally, a flap of cartilage called the epiglottis closes over the trachea to shield the airway. Laryngeal Changes During Respiration The larynx is a box of cartilage, which lies between the pharynx and the trachea. It corresponds to the "Adam's apple" in the neck. The larynx contains the vocal cords, which act like valves to control the flow of air from the mouth and nose to the trachea.

As mentioned above, these membranous bands protect against aspiration. By vibrating as air passes, they also produce the voice. The space between the vocal cords is the glottis. When the vocal cords are apart, the glottis is open and air passes through the larynx without vibrating the vocal cords. As muscles pull the vocal cords together, the glottis closes and sound is produced. The pitch of the sound is determined by the tension of the vocal cords. The trachea is an open tube which extends downward from the base of the larynx. Like the rest of the airway, it is lined by mucosa and is kept open by a series of cartilage arches. The trachea separates at the bottom into two branches (mainstem bronchi), leading to the left and right lungs. As the mainstem bronchi enter the lungs, they divide into smaller and smaller tubes. The entire network of these bronchi is called the bronchial tree. The smallest tubes are called bronchioles, which end in tiny air sacs known as alveoli. The alveoli are lined with small blood vessels (capillaries).

This allows oxygen to pass from the inhaled air into the bloodstream, while allowing carbon dioxide in the blood to be eliminated into the airway and exhaled. Epiglottis - definition of epiglottis by The Free Dictionary Epiglottis - definition of epiglottis by The Free Dictionary (ĕp′ĭ-glŏt′ĭs) n. pl. ep·i·glot·tis·es or ep·i·glot·ti·des (-glŏt′ĭ-dēz′) The thin elastic cartilaginous structure located at the root of the tongue that folds over the glottis to prevent food and liquid from entering the trachea during the act of swallowing. [Greek epiglōttis : epi-, epi- + glōttis, glottis; see glottis.] ep′i·glot′tal (-glŏt′l), ep′i·glot′tic (-glŏt′ĭk) adj.

epiglottis (ˌɛpɪˈɡlɒtɪs) n, pl -tises or -tides (-tɪˌdiːz) (Anatomy) a thin cartilaginous flap that covers the entrance to the larynx during swallowing, preventing food from entering the trachea ˌepiˈglottal, ˌepiˈglottic adj (ˌɛp ɪˈglɒt ɪs) n., pl. -glot•tis•es, -glot•ti•des (-ˈglɒt ɪˌdiz) a flap of cartilage behind the tongue that helps close the opening to the windpipe during swallowing. [1605–15; < Greek epiglōttís; see epi -, glottis ] ep`i•glot′tal, adj. ep·i·glot·tis (ĕp′ĭ-glŏt′ĭs) A thin, triangular plate of cartilage at the base of the tongue that covers the glottis during swallowing to keep food from entering the trachea.

epiglottis A cartilage flap behind the tongue that is closed during swallowing to stop food entering the larynx. ThesaurusAntonymsRelated WordsSynonymsLegend: ACTIONS OF THE PHARYNGEAL MUSCLES During swallowing, successive contraction of the superior, middle, and inferior constrictor muscles helps to propel the bolus (ball) of food down into the esophagus. In addition, contraction of the 3 longitudinal muscles of the pharynx helps to raise the pharynx, effectively aiding it in engulfing the bolus of food. In between acts of swallowing, the lowest fibers of the inferior constrictor are thought to act as a sphincter, guarding the entrance to the esophagus and preventing the entry of air into the digestive system. The LARYNX is an apparatus made up of cartilage, ligaments, muscles, and mucous membrane, which guards the entrance to the lower respiratory passages (trachea, bronchi, and lungs) and houses the vocal cords. Figure 4 shows the major cartilaginous and ligamentous structures which make up the larynx.

(Note that the hyoid bone is not usually considered as part of the larynx and is included in this figure strictly as an aid to orientation.) Before you consider the muscles associated with the laryngeal apparatus, pay very careful attention to the arrangement of the structural components shown in Figure 4, and realize that three major types of movement are possible: 1. MOVEMENT AFFECTING THE TENSION OF THE VOCAL CORDS. Since the vocal cords are attached to the arytenoid cartilages posteriorly and the thyroid cartilage anteriorly, regulation of vocal cord tension (and therefore pitch of the voice) is accomplished primarily by pivoting the thyroid cartilage forward or backward at the cricothyroid joint (Figure 51. 2. MOVEMENTS WHICH INCREASE OR DECREASE THE SIZE OF THE OPENING BETWEEN THE VOCAL CORDS (ABDUCTION OR ADDUCTION OF THE VOCAL CORDS). This action is best appreciated by imagining the larynx viewed from above, as is shown semi-schematically in Figure 6. Realize: I.

That the vocal cords on each side are covered with a mucous membrane, so that when they are abducted, relatively little air can pass either between them or around them. 2. The bases of the two arytenoid cartilages are L-shaped. The medial process of each is called the vocal process, and the vocal cords attach to it. The lateral process of each is called the muscular process, and most of the muscles which act to abduct or adduct the vocal cords attach to it. Abduction of the vocal cords may be accomplished either by externally rotating the arytenoid cartilages on a pivot located at the angle of the "L" (center panel, Figure 6), or by sliding the 2 arytenoid cartilages apart slightly (right panel, Figure 6). Realize that there is only 1 muscle which has an abductor action on the vocal cords, although there are several which act to adduct the cords. 3. MOVEMENTS WHICH CLOSE OFF THE ENTRANCE TO THE LARYNX, AS IN SWALLOWING.

Figure 7 below indicates with arrows the movements of the epiglottis and arytenoid cartilages which take place during swallowing to block off the entrance to the larynx, to prevent food from entering the larynx. Basically, the epiglottis is pulled down, and the arytenoid cartilages are pulled forward, toward the epiglottis. Realize that two other mechanisms which are independent of laryngeal movements per se also help to keep food from entering the larynx during swallowing. First, the larynx is raised, along with the pharynx, by the contraction of the longitudinal muscles of the pharynx. Second, the epiglottis also acts partly as a passive barrier to the movement of food, so that food tends to be funneled to either side of the larynx, into the PIRIFORM RECESSES and from there into the esophagus. Refer to Figure 9-56 in your atlas, which shows the pharynx opened up to reveal the interior of the pharynx, as seen from behind.

Locate the epiglottis, piriform recesses, and esophagus, and trace the path of a bolus of food from the back of the tongue into the esophagus. Figure 4. (On left) Side view illustrating the major cartilaginous and ligamentous structural features of the larynx. Shaded structures are imagined as seen through the thyroid cartilage or hyoid bone. Figure 5. (On right) Schematic drawing of the larynx as seen from the side to show how movement of the thyroid cartilage at the cricothyroid joint affects the tension of the vocal cords. From Basmajian, Grant's Method of Anatomy, p. 530. Figure 6. Schematic drawing of the larynx as seen from above showing the thyroid cartilage, the arytenoid cartilages, and the vocal cords. From Basmajian, Grant's Method of Anatomy, p. 532. Figure 7. Schematic drawing of the larynx as seen from the side. Arrows indicate the direction of movement of the epiglottis arytenoid cartilages which take place cluring swallowing.

OTHER STRUCTURAL FEATURES OF THE LARYNX Refer to Figures 9-78 and 9-79 in your atlas to appreciate several additional structural features which have been intentionally omitted from the previous discussion. These features (described below) are not particularly important to understanding movements of the larynx, but you will find it somewhat difficult to understand the appearance of the larynx as seen through a laryngoscope or on dissection, until you appreciate that: 1. Above and parallel to the vocal ligament or vocal cord on each side is a second ligament called the VESTIBULAR or VENTRICULAR LIGAMENT (Atlas Figure 9-78, right side). This ligament is not actively moved during vocalization, and is therefore referred to as a "false vocal cord." Nonetheless, this ligament (or the fold of mucous membrane which covers it) is a prominent feature when the larynx is examined with a laryngoscope. 2. The entire larynx is covered with a mucous membrane, which is given different names in its different parts, depending on the structures it covers over or runs between. (See Atlas Figure 9-78, left side.) 3.

The membrane running between the epiglottis and the arytenoid cartilages, called the QUADRANGULAR MEMBRANE, is reinforced by a small cartilage which is embedded in it, the CUNEIFORM CARTILAGE. 4. On each side, another small cartilage, called the CORNICULATE CARTHAGE, caps the arytenoid cartilage superiorly. N.B. Do not waste any time during the dissection seeking the cuneiform and corniculate cartilages, as finding them grill not significantly advance your understanding of the larynx. PARTS OF THE LARYNGEAL CAVITY The boundaries formed by the vestibular and vocal folds (see left side of Atlas Figure 9-78) divide the cavity of the larynx into three parts. These are illustrated schematically in Figure 8 below: 1. The VESTIBULE, which is the area above the vestibular folds. 2. The VENTRICLE, which is a pocket-like recess between the vestibular and vocal folds on both sides. 3. The INFRAGLOTTIC CAVITY, which is the area below the vocal folds. Figure 8.

Schematic diagram (coronal section) illustrating the 3 parts of the laryngeal cavity. Modified slightly from Basmajian, Grant's Method of Anatomy, p.532. There are two other terms you must know: 1. The GLOTTIS is the aperture formed by the vocal folds (analogous to the iris of the eye). 2. The RIMA GLOTTIDIS is the opening between the vocal folds (analogous to the pupil of the eye). Realize that the size of the rime glottidis is a major factor in determining how much air can enter the trachea and lungs. MUSCLES OF THE LARYNX Since you presumably already understand the possible movements of the larynx, understanding the actions of the laryngeal muscles should now be a relatively straightforward matter. The muscles will be presented in functional groups. 1 . MUSCLES WHICH AFFECT THE TENSION OF THE VOCAL CORDS. The CRICOTHYROID MUSCLES (illustrated in Figure 5) are the muscles primarily responsible for regulating the tension of the vocal cords.

The small VOCALES muscles, which lie parallel and inferior to the vocal cords (see Atlas Figure 9-74) control fine adjustment of vocal cord tension. 2. MUSCLES WHICH OPEN AND CLOSE THE RIMA GLOTTIDIS (ABDUCT AND ADDUCT THE VOCAL CORDS). Abductor: The posterior cricoarytenoid is the only abductor of the vocal cords. The actions of the horizontal and vertical fibers of the posterior cricothyroid muscle are illustrated in the center and right panels of Figure 6. Adductors: The major abductors of the vocal cords are the LATERAL CRICOARYTENOID, THYROARYTENOID, and ARYTENOIDEUS MUSCLES. The disposition of these muscles is illustrated in Figures 9 and 10 and in the left panel of Figure 6. 3. MUSCLES WHICH CLOSE OFF THE VESTIBULE OF THE LARYNX, AS HAPPENS DURING SWALLOWING. The muscles which are mainly responsible for closing off the vestibule are the ARYEPIGLOTTICUS, the THYROEPIGLOTTICUS, and the THYROARYTENOID.

Look at Figures 9 and 10 and try to understand how contraction of these muscles would exert a sphincter-like action on the vestibule to the larynx, drawing the epiglottis downward and backward, and the arytenoid cartilages forward, while keeping the vocal cords adducted. Figure 9. (On left.) Side view with part of the thyroid cartilage removed to show the muscles of the larynx. From Basmajian Grantts Method of Anatomy p. 531. Figure 10. (On right.) View from behind to show the muscles of the larynx. On the left side the posterior cricoarytenoid muscle has been removed. From Basmajian, Grant's Method of Anatomy, p.531. BLOOD SUPPLY TO THE LARYNX AND PHARYNX Blood is supplied to this region by the ascending pharyngea] arteries (pharynx only) and branches of the superior and inferior thyroid arteries (pharynx and larynx). NERVE SUPPLY TO THE LARYNX AND PHARYNX 1.

MOTOR INNERVATION OF THE MUSCLES OF THE PHARYNX AND LARYNX arises mainly from the CRANIAL DIVISION of the ACCESSORY NERVE (XI). Note, however, that these axons TRAVEL with those of the VAGUS NERVE, and are indistinguishable from it (see Figure 1 1). Exception: The STYLOPHARYNGEUS MUSCLE receives its motor innervation from the GLOSSOPHARYNGEAL NERVE (TX) (see Figure 12). Note that this is the ONLY muscle innervated by this nerve. Most of the muscles of the larynx receive their innervation via the RECURRENT LARYNGEAL BRANCH of the vagus nerve (see Figure 11 ). Exception: The CRICOTHYROID MUSCLE, which receives its innervation via the EXTERNAL LARYNGEAL NERVE. 2. SENSORY INNERVATION OF THE LARYNX AND PHARYNX. Pharynx: via the GLOSSOPHARYNGEAL NERVE (see figure 12). Larynx: via branches of the VAGUS NERVE (see Figure 11).

Above the vocal folds the sensory innervation of the larynx is via the INTERNAL LARYNGEAL NERVE. Below the vocal folds it is by way of branches of the RECURRENT LARYNGEAL NERVE. 3. PARASYMPATHETIC INNERVATION OF THE LARYNX AND PHARYNX is mainly by way of branches of the vagus nerve. Figure 11. (On left.) Distribution of the branches of the vagus nerve and the fibers of the cranial division of the accessory nerve which travel with it. Figure 12. (On right.) Distribution of the branches of the glossopharyngeal nerve. SPECIAL LYMPHATIC TISSUE OF THE PHARYNX Realize that the pharynx contains a "ring" of specialized lymphatic tissue designed to prevent the entry of pathogens into the digestive and respiratory tracts. This specialized lymphatic tissue is known as "tonsils" and is organized into three groups: 1. nasopharyngeal tonsils (adenoids), located in the nasal pharynx; 2.

palatine tonsils (tonsils), located between the palatoglossal and palatopharyngeal folds in the oral pharynx; and 3. lingual tonsils, located on the posterior surface of the tongue. The approximate location of these three groups of lymphoid tissue is indicated in Figure 13. Figure 13. Semischematic mid-sagittal section through the nose, mouth, end pharynx to illustrate the approximate position of the three groups of "tonsils".

Question: In anatomy, what is the flap of elastic cartilage that prevents food from going down the wrong tube?
Answer: Epiglottis