Section 3 Thyroid gland Copynight e The Me Graw.Hin companies, ine. Permission required for reproduction or display. Thyroid cartilage of larynx Cricoid cartilage of larynx Thyroid gland Trachea
Section 3 Thyroid Gland
(b) Section of thyroid gland Thyroid follicle Capsule of connective tissue C cells secrete Capillary calcitonin Follicular cells secrete Colloid is a thyroid hormone glycoprotein
I. Biological actions of Thyroid Hormones T, and T, bind with nuclear receptor, activate and initiate genetic transcription mrNA protein syntheSis in cytoplasmic ribosomes general increase in functional activity throughout the body
I. Biological Actions of Thyroid Hormones ◼ T3 and T4 bind with nuclear receptor, ◼ activate and initiate genetic transcription. ---- mRNA ◼ protein synthesis in cytoplasmic ribosomes ---- ◼ general increase in functional activity throughout the body
1. On Metabolism a Calorigenic action of thyroid hormones Effect on metabolism of protein carbohydrate fat
1. On Metabolism ◼ Calorigenic action of thyroid hormones ◼ Effect on metabolism of ◼protein ◼carbohydrate ◼fat
Calorigenic action increase O, consumption of most tissues in the body increasing heat production and BMr mechanism A: Enhances Nat-K ATPase activity B: Causes the cell membrane of most cells to become leaky to Na* ions
Calorigenic action ◼ increase O2 consumption of most tissues in the body, increasing heat production and BMR. ◼ mechanism ◼ A: Enhances Na+-K+ ATPase activity ◼ B: Causes the cell membrane of most cells to become leaky to Na+ ions