Thyroid gland

• Thyroid gland: highly vascular and butterfly-shaped
• Thyroid gland is located anterior and posterior to the what?

  larynx
• The 2 lobes of thyroid glands are joined by what?

  Isthmus
• Thyroid gland synthesizes what?

  Triiodothyronine (T3), thyroxine (T4) and Calcitonin
• Follicular cells secretes what?

  Triiodothyronine (T3) and Thyroxine (T4)
• Follicular cells range in shape from SQUAMOUS to LOW COLUMNAR
• Squamous: hypoactive
• low columnar: active
• what is the precursor for active thyroid hormone?

  thyroglobulin
• Parafollicular cell is also known as what because it produces what?

  C cell, calcitonin
• Follicular cells: smaller and darker
• parafollicular cells: larger and stain less
• Thyroid follicles: rounded epithelium with variable diameter
• Colloid: gelatinous acidophilic containing THYROGLOBULINS