All are derivatives of Rathke’s pouch EXCEPT?
**Core Concept**
Rathke's pouch is a precursor to the anterior pituitary gland, which develops from an ectodermal thickening in the roof of the mouth during embryonic development. The derivatives of Rathke's pouch are essential structures in the endocrine system.
**Why the Correct Answer is Right**
The anterior pituitary gland is formed from Rathke's pouch, and it plays a crucial role in regulating various bodily functions through the secretion of different hormones. The pituitary gland controls other endocrine glands, such as the thyroid, adrenal glands, and gonads. The development of Rathke's pouch is a critical process in the formation of the anterior pituitary gland.
**Why Each Wrong Option is Incorrect**
**Option A:** The posterior pituitary gland is not a direct derivative of Rathke's pouch. Instead, it develops from the infundibulum, a downgrowth of the diencephalon. The posterior pituitary gland stores and releases antidiuretic hormone (ADH) and oxytocin from the hypothalamus.
**Option B:** The adenohypophysis, also known as the anterior pituitary gland, is indeed a derivative of Rathke's pouch.
**Option C:** The neurohypophysis, also known as the posterior pituitary gland, is not a direct derivative of Rathke's pouch.
**Option D:** The intermediate lobe of the pituitary gland is a derivative of Rathke's pouch, but it is not as well-developed in humans as the anterior pituitary gland.
**Clinical Pearl / High-Yield Fact**
Remember that Rathke's pouch gives rise to the anterior pituitary gland, which is crucial for regulating various bodily functions through hormone secretion.
**Correct Answer:** C. The neurohypophysis, also known as the posterior pituitary gland, is not a direct derivative of Rathke's pouch.