Describe the microscopic structure of the thyroid gland?

Functional unit of the thyroid is the follicle: Outer sphere of cuboidal epithelial cells (thyrocytes) and thin basement membrane: Site of thyroglobulin production Filled with a protein rich core called colloid: Made up of thyroglobulin a large glycoprotein Serves as...

Which hormones are produced by the thyroid gland?

Hormone Thyroxine (T4) - carries 4 iodine atoms) Triiodothyronine (T3) - carries 3 iodine atoms) Reverse-triiodothyronine (r-T3) - formed by peripheral conversion of T3 Calcitonin Function Regulation of metabolism and growth Metabolically inactive Regulation of...

What are the functions of thyroid hormone (T3 & T4)?

Effects on Metabolism Increase basal metabolic rate of most tissues (Long duration of action):Increased heat productionIncreases cardiac metabolic rate:Ionotropic / chronotropic effectIncreased lipolysis & gluconeogenesis Effect on Beta Receptors Increases number...

Compare T3 and T4?

T3 T4 Active form of thyroid hormone - 3x more potent than T420% of T3 secreted directly from the thyroid80% converted peripherally from T4 Often referred to as the prohormone due to low biological coactivityApproximately 90% is converted in peripheral tissues to more...