Question

which of the following hormones is not secreted by the thyroid gland? a triiodothyronine b thyroid - stimulating hormone c thyroxine d calcitonin

Explanation:

• Triiodothyronine (\(T_3\)): Secreted by the thyroid gland. It helps regulate metabolism.
• Thyroid - stimulating hormone (TSH): Secreted by the anterior pituitary gland. Its role is to stimulate the thyroid gland to produce and release thyroxine (\(T_4\)) and triiodothyronine (\(T_3\)).
• Thyroxine (\(T_4\)): Secreted by the thyroid gland. It is involved in regulating growth, development, and metabolic rate.
• Calcitonin: Secreted by the parafollicular cells (C - cells) of the thyroid gland. It helps lower blood calcium levels.

Answer:

B. thyroid - stimulating hormone