THYROID GLANDSVerdeflor, Dungog, Nepomuceno

THYROID GLAND

The location of the thyroid gland in the neck, in front of the windpipe (trachea). The voice box (larynx) sits just above the thyroid.

THYROID (HUMAN ANATOMY)

Thyroid Gland The thyroid gland is part of the endocrine system

and is responsible for producing and releasing thyroid hormones into the bloodstream.

The thyroid is a butterfly-shaped gland that sits low on the front of the neck. Your thyroid lies below your Adam’s apple, along the front of the windpipe. The thyroid has two side lobes, connected by a bridge (isthmus) in the middle. When the thyroid is its normal size, you can’t feel it.

Brownish-red in color, the thyroid is rich with blood vessels. Nerves important for voice quality also pass through the thyroid.

Thyroid Gland The thyroid secretes several hormones,

collectively called thyroid hormones. The main hormone is thyroxine, also called T4. Thyroid hormones act throughout the body, influencing metabolism, growth and development, and body temperature. During infancy and childhood, adequate thyroid hormone is crucial for brain development.

Where is my thyroid gland?

The thyroid gland is located at the front of the neck just below the Adam's apple (larynx). It is butterfly-shaped and consists of two lobes located either side of the windpipe (trachea). A normal thyroid gland is not usually outwardly visible or able to be felt if finger pressure is applied to the neck. 

What does my thyroid gland do?

The thyroid gland produces hormones which regulate the body’s metabolic rate as well as heart and digestive function, muscle control, brain development and bone maintenance. Its correct functioning depends on having a good supply of iodine from the diet.  

The release of thyroid hormones from the thyroid gland is controlled by thyrotrophin-releasing hormone(TRH) from the hypothalamus in the brain and by thyroid stimulating hormone (TSH) produced by the pituitary gland. This forms part of a feedback loop called the hypothalamic-pituitary-thyroid axis. 

What hormones does my thyroid gland produce?

The thyroid gland produces thyroxine (T4), which is a relatively inactive prohormone and lower amounts of the active hormone, triiodothyronine (T3). Collectively, T3 and T4 are referred to as the thyroid hormones. Twenty percent of the body’s triiodothyronine is made by the thyroid gland; the other 80% comes from thyroxine converted by organs such as the liver or kidneys.

The thyroid gland also produces calcitonin from cells called C-cells. Calcitonin is understood to play a role in regulating calcium levels in the body, but its exact function in humans remains unclear. 

Thyroid Conditions

Goiter: A general term for thyroid swelling. Goiters can be harmless, or can represent iodine deficiency or a condition associated with thyroid inflammation called Hashimoto’s thyroiditis.

Thyroiditis: Inflammation of the thyroid, usually from a viral infection or autoimmune condition. Thyroiditis can be painful, or have no symptoms at all.

Hyperthyroidism: Excessive thyroid hormone production. Hyperthyroidism is most often caused by Graves disease or an overactive thyroid nodule.

Hypothyroidism: Low production of thyroid hormone. Thyroid damage caused by autoimmune disease is the most common cause of hypothyroidism .

Thyroid Conditions Graves disease: An autoimmune condition in which the

thyroid is overstimulated, causing hyperthyroidism. Thyroid cancer: An uncommon form of cancer, thyroid

cancer is usually curable. Surgery, radiation, and hormone treatments may be used to treat thyroid cancer.

Thyroid nodule: A small abnormal mass or lump in the thyroid gland. Thyroid nodules are extremely common. Few are cancerous. They may secrete excess hormones, causing hyperthyroidism, or cause no problems. 

Thyroid storm: A rare form of hyperthyroidism in which extremely high thyroid hormone levels cause severe illness.

SummaryGland Location Hormones

ReleasedFunction

Thyroid below the

voice box

Thyroxin,

Calcitonin

regulates body

metabolismand causes storage

of calcium in bones