Head & Neck

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    The head and neck region of the human body is shown in the figure figure (a) and the parts are briefly discussed below.

Neck:

In our body, the neck is the part of the body including the throat region, that distinguishes the head from our torso (trunk).

Mouth:

In our body, the mouth (oral cavity) is the entrance to the digestive system where food is broken into pieces by the teeth, saliva is excreted and local enzymes begin the digestion process.

Nose:

In our body, the nose is an organ that protrudes on the face that houses our nostrils, which admit and expel air for respiration in conjunction with the mouth. In our body, behind the nose is the olfactory mucosa and the sinuses. Behind the nose and nasalcavity, air next passes through the pharynx, shared with the digestive system, and then into the rest of the respiratory system.

Ear:

In our body, the Ear, is the anatomical organ that detects sound. In our body, the Ear acts as a receiver for sound, and plays a major role in both the sense of balance and body position. In our body, the ear, is part of the Auditory system, may be divided into three parts: the External ear, the  Middle ear, and the Inner ear.

Teeth:

In our body's mouth, teeth are part of the Skeletal System not counted as bones. Each tooth is made of enamel and dentin. In our body, the teeth are part of the Digestive System as an Accessory Organ along with the tongue, liver and pancreas.

Tongue:

In our body, the Tongue is a muscular hydrostat on the floor of the mouth which manipulates food for mastication. In our body, the Tongue is the primary organ of taste, as much of the upper surface of the tongue is covered in papillae and taste buds. In our body, the Tongue is sensitive and kept moist by Saliva, and is richly supplied with nerves and blood vessels. In our body, the Tongue a secondary function of the tongue is phonetic articulation. The tongue also serves as a natural means of cleaning one's teeth.

Face:

On our body's head, the face is a central sense organ complex, on the anterior surface of the head, including: the hair, forehead, eyebrow, eyelashes, eyes, nose, cheeks, mouth, lips, philtrum, teeth, skin, and chin.

Facial functions:

On our body, the Face has uses of expression, appearance, and identity amongst others, including the use of different senses like olfaction, taste, hearing, and vision.

Larynx:

In our body, the Larynx (voice box) is a hollow structure at the beginning of the trachea. The vocal cords extend across the opening of the Larynx. In our body, the Larynx (voice box)  houses the vocal folds, which are an essential component of phonation. The vocal folds are situated just below where the tract of the Pharynx splits into the Trachea and the Esophagus.

Pharynx:

In our body, the Pharynx is the part of the throat situated immediately posterior to (behind) the Mouth and naal cavity, and cranial, or superior, to the Esophagus, larynx, and trachea. In our body, the pharynx is divided into three distinct anatomic sections: the Nasopharynx, Oropharynx, and Hypopharynx.

Functions:

In our body, the pharynx is part of the Digestive System and the Respiratory System. In our body, the pharynx is important in Vocalization.

Salivary Gland:

Three major pairs of salivary glands supply the oral cavity: parotid, submandibular, and sublingual in the figure (b). These glands secrete saliva to assist in the process of digestion. The largest of the salivary glands are the parotid glands, which lie just below and in front of the ear. The parotid glands empty into the mouth through the parotid duct (also known as Stensen’s duct). The duct empties into the mouth through the parotid papilla, which is just opposite the maxillary second molar. The subman dibular glands are about the size of a walnut and lie on the inside of the mandible in the posterior area. They empty saliva into the mouth through the Wharton’s duct, which ends in the sublingual caruncles. The third set of glands and smallest are the sublingual glands, located on the floor of the mouth. These glands either empty directly into the mouth through the ducts of Rivinus or through the sublingual caruncles by means of the ducts of Bartholin. The ducts of the sublingual glands are similar in function to a “soaker hose.” There are also smaller minor salivary glands that are in the buccal, labial and lingual mucosa, the floor of the mouth, the posterior portion of the dorsal surface of the tongue, the soft palate, and the lateral (side) portions of the hard palate. The saliva from these glands is a mucous saliva.

Thyroid:

The thyroid gland is situated in the neck in front of the larynx and trachea at the level of the 5th, 6h and 7th cervical and 1st thoracic vertebrae. It is a highly vascular gland that weighs about 25 g and is surrounded by a fibrous capsule. It resembles a butterfly in shape, consisting of two lobes, one on either side of the thyroid cartilage and upper cartilaginous rings of the trachea. The lobes are joined by a narrow isthmus, lying in front of the trachea. The lobes are roughly cone-shaped, about 5 cm long and 3 cm wide. Two parathyroid glands lie against the posterior surface of each lobe and are sometimes embedded in thyroid tissue. Figure shows the thyroid gland and parathyroid glands fig (c)

Figure (c)

Iodine is essential for the formation of the thyroid gland hormones, thyroxine (T4) and triiodothyronine (T3). The body's main sources of iodine are seafood, vegetables grown in iodine-rich soil and iodinated table salt in the diet. The thyroid gland selectively takes up iodine from the blood, a process called iodine trapping. The parathyroid glands secrete parathyroid hormone (PTH, parathormone). Secretion is regulated by the blood level of calcium. When this falls, secretion of PTH is increased and vice versa.


Questions:

1) Larynx is called as

a) Voice box

b) Wind pipe

c) Auditory sytem

d) All


What is the name of hormone secreted by parathyroid?

a) T3 and T4

b) Bile

c) Paratharmone (PTH)

d) all


References:

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