The thyroid gland is subdivided by capsular septa into lobules containing follicles. A classic negative feedback loop controls the regulation of thyroid hormone levels. The thyroid, or thyroid gland, is an endocrine gland in the neck consisting of two connected. Background thyroid peroxidase tpo is essential for physiological function of the thyroid gland. The medial region, called the isthmus, is flanked by wingshaped left and right lobes. The thyroid gland is composed of 2 lobes connected by an isthmus. The primary function of the thyroid is the production of the iodinecontaining thyroid. Ultrasound of the thyroid may be used to reveal whether structures are solid or filled with fluid. Grossly, the gland appears brownishred and the left and right lobes are connected by an isthmus. The functional unit of the thyroid gland is the follicle, which is composed of epithelial cells arranged as hollow vesicles of various shapes ranging in size from 0. Thyroid gland is a twolobed gland that wraps around the trachea and is located at the base of the neck in vertebrate animals.
Thyroid gland structure, function and pathology american society. Selenium is essential for normal thyroid hormone metabolism being involved with. Pdf thyroid gland is a part of the bodys endocrine system. T3 is so named because it contains three atoms of iodine per molecule and t4 contains four atoms of iodine per molecule. This article will take a look at both the structure and function of the thyroid gland. Collect iodine, synthesis of thyroglobulin and ths and release of ths. The thyroid gland is the endocrine gland responsible for producing thyroid hormone, a regulator of growth, development, and basal metabolic rate, and calcitonin, a regulator of calcium homeostasis described in chapter 8. Each of the thyroid lobes are embedded with parathyroid glands, primarily on their posterior surfaces. It is the largest organ specialized for endocrine function in human body.
Follicles surrounded by capillaries follicle cells filled with colloid colloid is thyroglobulin and stored thyroid hormone follicle cells. These septa also serve as conduits for blood vessels. The structures of the two thyroid hormones, triiodothyronine t3 and thyroxine. Anatomy, physiology and pathology of the thyroid gland.
The function of the thyroid gland is to produce and store thyroid hormones. Structure and function of thyroid gland assignment point. The thyroid gland is a small organ located in the front of your neck. Two hormones of the thyroid gland, t4 thyroxine and t3 triiodothyronine, help the body to produce and regulate the hormones adrenaline. The primary function of the thyroid gland or thyroid is the production of the iodinecontaining thyroid hormones, triiodothyronine t3 and thyroxine t4 and the peptide hormone calcitonin.
It is surrounded by a dense irregular collagenous connective tissue capsule, in which posteriorly the parathyroid glands are embedded. There are about three million follicles in the adult human thyroid gland. Pdf on jan 1, 2018, salvatore benvenga and others published thyroid gland. Anatomy and physiology find, read and cite all the research. Epithelial cells lining each follicle may be cuboidal or. The thyroid gland is located immediately below the larynx on. Iodine is the trace element that is most likely to influence thyroid function since it is an. A butterflyshaped organ, the thyroid gland is located anterior to the trachea, just inferior to the larynx. The primary function of the thyroid is the production of the iodine containing thyroid hormones. The thyroid gland covers the windpipe from three sides. The thyroid gland basic structure and function of the thyroid gland lobes and the connecting isthmus highly vascularized.
May, 2020 the thyroid gland is a bilobular endocrine gland that is found in the neck, anterior and inferior to the larynx. Pdf thyroid gland and its rule in human body researchgate. It has a relatively simple structure, yet has a complex function in regulating the metabolism of your body. The structures of the two thyroid hormones, triiodothyronine t3 and thyroxine t4, are shown in figure 1. To protect the rights of the author s and publisher we inform you that this pdf is an uncorrected proof for internal business use only by the author s. The thyroid gland is located immediately below the. Chapter 7 the thyroid gland introduction the thyroid gland is the endocrine gland responsible for producing thyroid hormone, a regulator of growth, development, and basal metabolic rate, and calcitonin, a regulator of calcium homeostasis described in chapter 8. Thyroid epithelia form follicles filled with colloid a proteinrich.
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