Video Transcript
Which of the following best
explains why the pituitary gland is often referred to as the master gland? (A) It controls the functions and
secretions of many other endocrine glands. (B) It controls most of the major
functions of the brain. (C) It receives communication from
all other endocrine glands. Or (D) it is the last endocrine
gland to form during fetal development.
This question asks us about an
important endocrine gland of the body, the pituitary gland. The pituitary gland is one of the
endocrine glands of our body, such as the thyroid gland, the adrenal glands, or the
gonads, just to name a few. The pituitary gland is as little as
a pea, attached to the bottom of the brain. Like the other endocrine glands of
the body, the pituitary gland secretes hormones that are released in the bloodstream
to reach their targets and regulate many body functions. But the pituitary gland stands out
among the other endocrine glands and is often referred to as the master gland. Why is that said?
Let’s have a closer look at the
structure and functions of the pituitary gland. The pituitary gland is made of two
main lobes in humans, the anterior lobe and the posterior lobe. These two lobes are different in
their structure, and they both release the pituitary hormones.
The pituitary hormones can be
categorized into two groups, the tropic and the nontropic hormones. The tropic hormones act on another
endocrine gland of the body. And the nontropic hormones have a
direct effect on various tissues of the body. For example, growth hormones, GH,
is a nontropic hormone that has a direct effect on bones and muscles to induce their
growth. However, TSH, which stands for
thyroid-stimulating hormone, is an example of a tropic hormone. It stimulates the thyroid gland to
release other hormones that will modify our metabolism.
In fact, the pituitary gland
releases many tropic hormones that target other endocrine glands, such as the
adrenal glands or the gonads. This is why the pituitary gland is
often referred to as the master gland. By controlling many other endocrine
glands, it can control various functions of our body: our metabolism, blood
pressure, or our reproduction.
Our correct answer is thus answer
(A). The pituitary gland is often
referred to as the master gland because it controls the functions and secretions of
many other endocrine glands.