The tongue, a fleshy and agile organ situated in the oral cavity, is a truly remarkable biological wonder. With complex anatomy of tongue and unique properties, it performs a variety of extraordinary functions, making it one of the most versatile organs in the human body. The tongue’s anatomy consists of an intricate network of intrinsic and extrinsic muscles, intricate lingual arteries, and a wide range of sensory receptors, including taste buds, thermal receptors, and mechanoreceptors. These features enable the tongue to perform a multitude of exceptional functions that contribute to our overall health and well-being.
One of the most notable functions of the tongue is its role in gustation or taste perception. The tongue is covered with tiny papillae that house taste buds capable of detecting a wide range of flavors, from sweet and salty to bitter and sour. In addition to its taste buds, the tongue also contains thermal receptors that can detect temperature and mechanoreceptors that can sense texture.
Beyond its sensory functions, the tongue plays a vital role in speech production, working in conjunction with the lips, teeth, and palate to produce an array of complex sounds and form words. It is also essential in the initial stages of digestion, where it helps to mix food with saliva and form it into a bolus that can be safely swallowed.
In this article, we shall delve into the various parts of the tongue and their respective functions, providing you with a comprehensive understanding of this vital organ.
Parts of a Tongue Diagram
Parts of a Tongue
- Apex or tip
- Underside or Ventral Surface
- Circumvallate Papillae
- Foliate Papillae
- Filiform Papillae
- Fungiform Papillae
- Taste Buds
- Lingual Frenulum
- Hypoglossal Nerve
- Lingual Artery and Vein
- Salivary Glands
- Sublingual Gland
- Submandibular Gland
- Lingual Tonsils
Muscles of Tongue
- Intrinsic muscles
- Superior Longitudinal
- Inferior Longitudinal
- Extrinsic muscles
Tongue Anatomy: Parts & Functions
Apex or Tip
The apex or tip of the tongue is the part of the tongue that we use to lick our lips, eat ice cream, and make certain speech sounds. It is also the most sensitive part of the tongue, containing the highest concentration of taste buds.
The tip of the tongue can detect even the slightest differences in taste, such as between different types of salt or sugar. The tongue’s surface contains small bumps called papillae that house the taste buds. Among them, the papillae located at the tip of the tongue are the smallest and most densely packed, which makes it the ultimate tool for taste testing.
The body of the tongue is a muscular powerhouse responsible for many essential functions, such as chewing and swallowing food, shaping sounds during speech, and helping to maintain oral hygiene.
The tongue’s body is made up of a complex arrangement of muscles that work together to create its various movements, including contraction, relaxation, and elongation.
Interestingly, the tongue is one of the strongest muscles in the body relative to its size, with a force of up to 0.25 Newtons, making it capable of generating some impressive biting and chewing power.
The root of the tongue is a crucial but often overlooked part of this complex muscle. It is responsible for anchoring the tongue in place and helping to stabilize it during speech and swallowing.
The root of the tongue also contains several critical structures, such as the lingual tonsils, which are part of the immune system and help to protect the body against infections.
Additionally, the root of the tongue is the site of several cranial nerves involved in vital functions such as taste, touch, and motor control.
The dorsum of the tongue is the upper surface that faces the roof of the mouth. It is covered with tiny bumps called papillae that give the tongue its unique texture.
There are four different types of papillae on the dorsum of the tongue, each with its unique structure and function.
These include the fungiform papillae, which are responsible for detecting sweet and sour tastes the filiform papillae. These are responsible for detecting texture and temperature and the circumvallate and foliate papillae, which are primarily responsible for detecting bitter tastes.
The dorsum of the tongue is also a vital tool for speech production, as it plays a crucial role in shaping sounds and vowels.
Underside or Ventral Surface
The ventral surface or underside of the tongue is a remarkable area that plays an essential role in our oral health. Not only does it contain a rich network of blood vessels and nerves that allow us to perceive basic tastes. But it’s also home to the sublingual glands, which produce saliva.
These glands are the smallest of the three salivary glands and are responsible for secreting a thin, slippery fluid that helps lubricate and moisten the mouth. They are also involved in breaking down carbohydrates, and neutralizing acids that can damage our teeth.
Interestingly, the ventral surface of the tongue is not only essential for our oral health but can also be a critical site for medical diagnosis.
The mucous membrane of the tongue comprises tiny bumps, known as papillae, which play a crucial role in our perception of taste and texture. There are four types of papillae, namely circumvallate, foliate, filiform, and fungiform, each with its distinct structure and function.
The circumvallate papillae, the biggest papillae located at the back of the tongue, are protected by a spherical trench lined with mucus-secreting cells. This mucus acts as a guard against stomach acids, safeguarding the papillae from harm.
In contrast, the foliate papillae, located on the sides of the tongue, are distinct in both structure and function. These ridges or folds house specialized crypt cells that contribute to the tongue’s immunological response.
The lymphoid tissue within these crypts generates immune cells that protect the tongue from infections and other harmful substances.
The filiform papillae, which are the most abundant, sense temperature and texture. They are covered with keratinized epithelial cells that protect against abrasion and injury during chewing and swallowing.
The fungiform papillae, scattered throughout the tongue’s surface, are responsible for detecting the tastes of umami and sweetness. These papillae contain taste buds, specialized cells that can detect even the smallest amounts of sweet and umami components in food.
Surrounding these taste buds are sensory nerve fibers that send signals to the brain, enabling us to perceive the flavor of food.
Taste buds are nature’s way of letting us experience the world through our tongues. These small sensory organs are capable of seeing a diverse range of flavors, from the sweetness of sugar to the bitterness of coffee.
The taste buds reside in small bumps on the surface of the tongue called papillae, which vary in shape and size based on their location. Specialized cells called taste receptor cells are responsible for detecting specific tastes.
Interestingly, taste buds are not just limited to the tongue; they are also found in other parts of the mouth and throat. These tiny structures not only allow us to taste food but also play a crucial role in detecting toxins and preventing us from consuming harmful substances.
The lingual frenulum, also known as the tongue tie, is a small fold of tissue that connects the tongue to the floor of the mouth. This structure plays a critical role in the movement and stability of the tongue during speech and swallowing.
In some cases, the frenulum can be too short or too tight, causing difficulty with these functions. However, recent research has shown that the frenulum may also be associated with other bodily functions, such as breathing and sleep. Some studies have suggested that a tight frenulum may contribute to snoring and sleep apnea.
These muscles are responsible for some of the most intricate movements in the human body. These four small muscles are totally contained within the tongue and work together to shape and move this organ.
The superior longitudinal muscle, located along the top of the tongue, is responsible for elevating and retracting the tip of the tongue. This muscle is also involved in the formation of specific speech sounds, such as the “L” sound in “love.”
Interestingly, this muscle is thicker and healthier in musicians and singers, as their profession requires more precise control over the tongue.
The inferior longitudinal muscle, located at the bottom of the tongue, is responsible for pulling the tip of the tongue downward and forward. This muscle is involved in speech formation sounds such as the “R” sound in “red.”
Interestingly, the size and strength of this muscle can vary between individuals, affecting their ability to pronounce certain speech sounds.
The transverse muscle is a horizontal muscle that runs across the tongue and is responsible for narrowing and elongating the tongue. This muscle is involved in the formation of speech sounds such as the “sh” sound in “shoe.”
Incredibly, some people are born with a double transverse muscle, giving them increased control over the shape and movement of their tongue.
The vertical muscle runs down the center of the tongue and is responsible for flattening and widening the tongue. This muscle is crucial for swallowing, as it helps to move food and liquid to the back of the mouth.
Interestingly, the size and strength of this muscle can be affected by particular medical conditions, leading to difficulty swallowing.
The genioglossus muscle stands out from all other muscles due to its unparalleled strength and size, making it the large and most potent tongue muscle. Its exceptional strength enables it to perform amazing functions, such as the ability to protrude the tongue out of the mouth and retract it deep into the throat.
However, in rare instances, the genioglossus muscle may become enlarged, obstructing the airway, which results in a severe medical condition known as obstructive sleep apnea.
It comes with a configuration of fibers that endow it with unparalleled versatility in the realm of tongue manipulation. Despite its slim and diminutive appearance, this powerhouse muscle is capable of performing a dizzying array of movements, including retraction, depression, flattening, and widening of the tongue.
The hypoglossal nerve innervates the hyoglossus muscle, which is a remarkable privilege. This nerve is incredibly complex and dense, showcasing the astonishing intricacies of the human body.
The styloglossus muscle, besides contributing to tongue movement and shape, has a fascinating embryological origin. This muscle develops from the second pharyngeal arch, which also gives rise to the stapes bone in the ear and the stylohyoid ligament in the neck.
The styloglossus muscle is also one of the few muscles in the body that can cause referred pain to the ear due to its proximity to the auriculotemporal nerve.
The palatoglossus muscle boasts an exceptional biological trait not commonly observed in other muscles: its distinct ability to contract independently of the other muscles of the tongue.
Furthermore, this remarkable muscle collaborates with the soft palate to effectively seal off the nasal cavity during swallowing, thus averting the ingress of food into the respiratory tract.
The palatoglossus muscle also exhibits a singular embryonic origin, arising from the fourth pharyngeal arch, the same structure that gives rise to the thyroid cartilage in the larynx. Such distinct biological features make the palatoglossus muscle truly exceptional in the realm of muscular anatomy.
The hypoglossal nerve is a mighty cranial nerve responsible for controlling the intricate movements of the tongue. This nerve originates from the brainstem and travels down through the neck, branching out to innervate the tongue muscles.
Without this nerve, we would not be able to articulate words, chew food, or swallow. Interestingly, recent studies have shown that the hypoglossal nerve may also play a role in controlling breathing during sleep. This nerve is critical for the normal functioning of the tongue and the overall body health.
Lingual Artery and Vein
The lingual artery and vein are two vital blood vessels that supply and drain blood from the tongue. These vessels run along the underside of the tongue, alongside the lingual nerve.
The lingual artery branches off from the external carotid artery, which is one of the major arteries that supply blood to the head and neck. This lingual vein drains into the internal jugular vein, which is one of the primary veins that return blood from the head and neck to the heart.
The lingual artery and vein are essential for the nourishment and oxygenation of the tongue, without which the tongue would not be able to function properly.
The tongue is one of the most important organs in the human body responsible for a variety of functions, including taste, speech, and digestion. However, did you know that the tongue relies heavily on the help of the salivary glands to perform its functions effectively?
The salivary glands are a group of three pairs of glands, including the parotid, sublingual, and submandibular glands, located in the oral cavity that produces saliva, a vital fluid for the process of digestion.
Saliva contains enzymes such as amylase, lipase, and protease that help break down carbohydrates, fats, and proteins, respectively, in the mouth, making them easier to digest further down the digestive system.
In addition, saliva helps to moisten food, making it easier to swallow, and contains antimicrobial agents that help to prevent infections in the mouth.
The sublingual gland is one of the three pairs of salivary glands located beneath the tongue. Although small, it is crucial for the proper functioning of the tongue and the oral cavity.
Unlike the other salivary glands, the sublingual gland produces a different type of saliva that is thicker and more mucous-like, containing a glycoprotein called mucin.
Mucin helps to protect and lubricate the oral cavity, acting as a barrier against potentially harmful pathogens and toxins that may enter the body through the mouth. The sublingual gland also contains a large number of mucus-secreting cells, which further aids in lubrication and the process of swallowing.
The submandibular gland is the second-largest salivary gland, located below the floor of the mouth in the lower part of the jaw. This gland produces approximately 70% of the total volume of saliva produced by the salivary glands, making it a crucial component of the digestive system.
The submandibular gland produces a mixture of both mucous and serous saliva, which helps to lubricate the oral cavity and begin the process of breaking down carbohydrates and fats.
Additionally, it contains a large number of ducts that empty saliva into the mouth, and its function is regulated by the autonomic nervous system.
The lingual tonsils are small, unique lymphoid tissues located at the base of the tongue, making them an essential component of the immune system.
Although not visible without special instruments, these tissues play a vital role in protecting the body against infections that may enter through the mouth.
The lingual tonsils are made up of small masses of lymphoid tissue containing immune cells such as lymphocytes and macrophages. These immune cells work together to detect and destroy foreign substances such as bacteria and viruses that may enter the body through the mouth.
In addition, the lingual tonsils help in the process of swallowing by providing a barrier between the oral cavity and the pharynx, preventing food and liquid from entering the airways during swallowing.
- Complete Guide to Mouth Anatomy: Learn Parts, Names & Diagram
- Complete Guide to Tooth Anatomy: Learn Parts, Names & Diagram
- Complete Guide to Thumb Anatomy: Parts, Names & Diagram
- Shoulder Anatomy: Ultimate Guide to Parts, Names, Functions & Diagram
- Complete Guide to Nail Anatomy: Parts, Names, Functions & Diagram
- Ultimate Guide to Biceps Anatomy: Parts, Names, Functions & Diagram