Learning Objectives

• Describe the structure of the thyroid gland
• Identify the steps in thyroid hormone biosynthesis
• Explain the mechanism of action of thyroid hormones
• Describe the role of the hypothalamus and pituitary in regulating thyroid function
• Describe the role of TSH in thyroid hormone biosynthesis
• Describe the major actions of thyroid hormones
• Explain the causes and consequences of excess and deficiency of thyroid hormones

Thyroid Gland

• what are the structural features of the thyroid gland?
• what are the functions of the thyroid gland?

Thyroid Hormones

• what are some characteristics of T3?
• what are some characteristics of T4?
• what is rT3?
• stimulating factors?
• inhibiting factors?
• chemical nature?
• steps of biosynthesis?