Which organ is responsible for secreting adrenocorticotropic hormone?

The anterior lobe of the pituitary gland is the organ responsible for secreting adrenocorticotropic hormone (ACTH). ACTH plays a critical role in the body's stress response by stimulating the adrenal cortex to produce corticosteroids, particularly cortisol. This hormone helps manage stress and regulates metabolism, immune response, and various other physiological functions.

The anterior pituitary is composed of various specialized cells that produce different hormones, including ACTH, which is secreted in response to corticotropin-releasing hormone (CRH) from the hypothalamus. This feedback loop is essential for maintaining hormonal balance and coordinating the body’s response to stress.

Other organs listed, such as the posterior lobe of the pituitary gland, the adrenal medulla, and the thyroid gland, have distinct functions and hormone production profiles that do not include the secretion of ACTH. The posterior lobe is primarily involved in storing and releasing hormones produced in the hypothalamus, rather than producing hormones itself. The adrenal medulla secretes adrenaline and noradrenaline, which are critical for the fight-or-flight response, while the thyroid gland primarily regulates metabolism through hormones like thyroxine and triiodothyronine.