The thyroid gland is a small, butterfly-shaped gland located in the neck and covers the anterior surface of the trachea. The gland has two lateral lobes connected by a thin tissue mass called the isthmus. Internally, each lobe comprises many small spherical structures known as thyroid follicles, surrounded by a network of blood vessels.
The follicles have a central cavity lined by simple cuboidal to squamous epithelial cells called follicular cells. These cells produce the glycoprotein...

Low blood levels of the thyroid hormones — triiodothyronine (T3) and thyroxine (T4) — signal the hypothalamus to release the thyrotropin-releasing hormone (TRH). TRH then reaches the pituitary gland and stimulates the release of thyroid-stimulating hormone(TSH) into the bloodstream.
Upon reaching the thyroid gland, TSH stimulates the follicular cells' active uptake of iodide ions from the blood. The ions diffuse to the apical surface of the cells and are oxidized to iodine. The...

The two pairs of parathyroid glands embedded within the posterior surface of the thyroid gland are restricted by a dense capsule around them. These glands comprise two distinct cell populations—parathyroid oxyphil and parathyroid principal cells- pivotal in calcium homeostasis.
Oxyphil cells, whose functions remain elusive, emerge during late puberty, adding a layer of complexity to the parathyroid gland's intricacies. In contrast, principal parathyroid cells undertake a vital role by...

The thyroid hormone (TH) plays a pivotal role in the intricate orchestration of physiological processes, exerting profound effects on development, metabolism, and homeostasis throughout different life stages.
TH is indispensable for the normal development and maturation of the skeletal, muscular, and nervous systems during fetal and childhood growth. It facilitates bone mineral turnover and regulates protein synthesis in developing tissues, contributing significantly to overall growth and...

The hyoid bone is a small U-shaped bone located in the upper neck at the level of the inferior mandible, with its tips pointing posteriorly. It does not directly articulate with any other bone in the body. The hyoid acts as the attachment site for the tongue, the larynx, and the pharynx. It is held in position by a series of small muscles attached from above or below. These muscles help to move the hyoid up/down or forward/back in coordination with movements of the tongue, larynx, and pharynx...

The human tongue is a fascinating and complex organ, responsible for various essential functions such as swallowing, speech, and taste. It is also subject to various conditions and diseases. In this article, we delve into the anatomy of the tongue, its roles, and some common conditions that can affect it.
Anatomical Position in the Oral Cavity
The tongue is located within the oral cavity, also known as the mouth. It is attached to the floor of the mouth by a fold of mucous membrane called the...