This chapter expands on what you have learned about the
functions of the hypothalamus (13.7).
You will see more examples of how homeostatic feedback
loops help regulate body functions (4.10).
You will also see how certain proteins in cell plasma mem-
branes function in physiological processes (3.4)—in this
case, by serving as receptors for hormone molecules.Key ConCepts
LinKs to earLier ConCepts
285How Hormones Work
Hormones bind to and activate
receptors on target cells. Their
signals are converted into forms
that work inside target cells to
bring about a response. Sections
15.1–15.2Sultan Kosen is 8 feet, 3 inches tall—likely the
tallest living person in the world. A tumor on his pituitary gland—
a vital organ of the endocrine system—resulted in too much
growth hormone circulating in his blood. Medical treatment that
included brain surgery at the University of Virginia finally halted
his growth and has allowed him to return to his life as a farmer
in his native Turkey. In this chapter we focus on how hormones
help regulate growth and many other body functions essential to
everyday health and well-being.All images: © Cengage Learningthe endoCrine system
15 The Endocrine System
15 The Endocrine System
Glands and tissues of the endocrine
system release most hormones. The
hypothalamus and pituitary glands
control much of this activity. Major
health concerns can result from
endocrine system disorders, includ-
ing disruptions of normal bodily
growth and metabolism. Sections
15.3 –15.11connEcTionS:
The Endocrine System
in Homeostasis
S e c t i o n 15 .12homeostasis preview
The endocrine system works in concert with the nervous
system to adjust many body functions. Hormones generally
govern long-term events such as growth and metabolism.ZUMA Press, Inc./AlamyCopyright 2016 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s).