Which part of the pituitary gland is responsible for secreting "effector" hormones?

The posterior pituitary gland is indeed responsible for the secretion of specific hormones, primarily oxytocin and vasopressin (also known as antidiuretic hormone, ADH). These hormones are released directly into the bloodstream from the nerve endings of hypothalamic neurons that extend into the posterior pituitary. While the posterior pituitary itself does not produce these hormones, it stores and releases them, acting as an important site for hormonal regulation in the body.

In contrast, the anterior pituitary gland secretes a different set of hormones, known as tropic hormones, which stimulate other endocrine glands to produce their own hormones. For example, hormones such as thyroid-stimulating hormone (TSH) and adrenocorticotropic hormone (ACTH) influence the thyroid gland and adrenal cortex, respectively, rather than acting directly as effector hormones.

The thyroid gland and adrenal cortex, while crucial components of the endocrine system, are not parts of the pituitary gland and have different roles related to hormone production and regulation within the body. Hence, the anterior pituitary is often recognized for its role in stimulating other glands, while the posterior pituitary functions more directly in regulating body processes through the release of its hormones.