Video Transcript
Thyrotropin in as an example of a
tropic hormone released from the pituitary gland. What is a tropic hormone? (A) A hormone that is insoluble in
the body. (B) A hormone that is transmitted
via the lymphatic system rather than the bloodstream. (C) A hormone that is only released
in response to stress. Or (D) a hormone that influences
the activity and secretions of other endocrine glands.
The pituitary gland is often
referred to as the master gland, mainly because this endocrine gland releases
hormones that target other endocrine glands in the body. We can see some of these endocrine
glands in this diagram of the endocrine system. Through their effects on other
endocrine glands, pituitary gland hormones can control the release of various other
hormones and indirectly control many more functions of the body. One example of a pituitary hormone
is thyrotropin, which you might know better as TSH, or thyroid-stimulating
hormone.
Thyrotropin stimulates the thyroid
gland to control the secretion of various thyroid hormones. In turn, these hormones regulate
many target tissues in the body. Thyrotropin in is a typical example
of a tropic hormone, which is a hormone that influences the activity and secretion
of other endocrine glands. The suffix -tropin and the
adjective tropic mean in ancient Greek to change or to turn. So if you meet the suffix in the
name of a hormone, you can guess its function.
Thyrotropin is a hormone that
changes the activity of the thyroid. Gonadotropin is a hormone that
changes the activity of the gonads. And ACTH, which is short for
adrenocorticotropic hormone, is a hormone that changes the activity of the cortex of
the adrenal glands. Therefore, we’ve worked out the
answer to our question that a tropic hormone is a hormone that influences the
activity and secretions of other endocrine glands.
