Given below is the outline of the human body showing the important glands: Given below is the outline of the human body showing the important glands:
Why is the part labelled 1 called the master gland? Which part of the forebrain controls the gland labelled 1?
Topic: Pituitary as the master gland
Answer
The PITUITARY is called the master gland because it secretes TROPIC HORMONES that CONTROL THE OTHER ENDOCRINE GLANDS — TSH controls the thyroid, ACTH the adrenal cortex, and FSH and LH the gonads.
It is itself controlled by the HYPOTHALAMUS, a part of the forebrain, to which it is attached by a stalk called the infundibulum.
Both halves must be answered: WHY it is the master gland, and WHAT controls it.
A TROPIC hormone is one whose TARGET is another ENDOCRINE GLAND rather than a body tissue. Listing two or three examples proves the point.
THE SECOND HALF IS THE INTERESTING ONE: the "master" has a master of its own. The HYPOTHALAMUS controls the pituitary, and since the hypothalamus is part of the BRAIN, this is the point at which the NERVOUS and ENDOCRINE systems meet — which is how emotion and stress can alter hormone levels.
It is also why the POSTERIOR pituitary does not actually MAKE its two hormones: ADH and oxytocin are produced in the hypothalamus and merely stored and released by the posterior lobe.