Download Name: Period: ______ Ch 9: The Endocrine System Objectives

Name: __________________________________________
Period: _________
Ch 9: The Endocrine System
Objectives:
Students will be able to:
 Define hormone and target tissue
 Describe how hormones bring about their effects in the body
 Explain how various endocrine glands are stimulated to release their hormonal
products
 Describe the difference between endocrine and exocrine glands
 Identify the major endocrine glands and tissues
 List hormones produced by the endocrine glands and their general functions
 Describe the effect of aging on the endocrine system and body homeostasis.
The endocrine system is the ______________ messenger system of the body. The speed
of the endocrine system is much slower than the fast impulse of the _____________
system. This system uses _________________ messages (_________________) that are released
into the blood. Hormones control several major processes, such as:
 _____________________________________
 _____________________________________
 _____________________________________
 _____________________________________
 _____________________________________
The Endocrine System and Hormone Function—An Overview
Compared to other organs of the body, the organs of the endocrine system are
small and lack the structural or anatomical continuity of most organ systems.
However, functionally the endocrine organs are very impressive, and when their role
in maintaining body homeostasis is considered, they are true giants.
The Chemistry of Hormones
The hormones produced and secreted by these organs have massive power.
Hormones are chemical substances that are produced by specialized _________. These
cells _____________ hormones into extracellular fluids. ____________ transfers hormones to
target sites in which these hormones ___________ the activity of other cells. Although
many different hormones are produced, nearly all of them can be classified as either:
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 _______________________________ (proteins, peptides, and amines)
 _________________— made from cholesterol(include the sex hormones made
from gonads, and hormones produced by the adrenal cortex)
 ___________________— made from highly active lipids
Mechanisms of Hormone Action
Although blood-borne hormones circulates all the organs of the body, I given
hormone affects only certain _____________ or _____________ (target cells or organs). In
order for target cells to respond to the hormone, it must have specific ____________
________________ on its plasma membrane, or in it’s interior so with that hormone can
attach. When this binding occurs, the hormone _______________ the working of the cells.
The time hormone comes from a Greek word meaning “to arouse.” Hormones
are arouse or bring about their effects on the body’s cells primarily by altering
cellular activity—by increasing or decreasing the rate of a normal, or usual metabolic
process rather then by stimulating and new one. The changes that follow hormone
binding depend on the specific hormone and the target cell type, but typically one or
more of the following occurs:
 ______________________________________________________________________
 ______________________________________________________________________
 ______________________________________________________________________
 ______________________________________________________________________
Despite a huge variety of hormones, there are two mechanisms by which hormones
trigger changes in cells: steroid hormone action and nonsteroid hormone action.
Steroid Hormone Action
Being lipid soluble molecules, the steroid hormones
_____________ through the plasma membrane of target
cells. The hormone enters the ____________, then
binds to a specific _____________ receptor within the
nucleus. The hormone receptor complex then __________
to specific sites on the cell’s ________. This in turn
_________________ genes that result in synthesis of new
proteins.
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Nonsteroid Hormone Action
Nonteroid hormones (protein and peptide hormones)
are unable to enter the target cells, they instead utilize
a second-messenger system. The hormone binds to a
membrane ________________. The hormone does not enter
the ________. The binding sets off a series of __________________
that activates an enzyme. The enzyme _________________ a
reaction that produces a ________________ __________________
molecule. The molecule oversees additional intracellular
_______________ to promote a specific response.
Control of Hormone Release
Hormones levels in the blood are maintained by _______________ feedback mechanisms.
A ______________ or _______ hormone levels in the blood triggers the release of more
hormone. Hormone release that’s once the appropriate level in the blood is reached.
The stimuli that activate the endocrine organs fall into three major categories:
1. __________________
2. __________________
3. __________________
The most common stimulus is a ________________ stimulus, in which
endocrine glands are activated by other __________________. For
example, hypothalamic hormones stimulate the anterior pituitary
gland secrete it’s hormones, and many into your pituitary
hormones stimulate other endocrine organ to release their hormones
into the blood.
Change of _________ levels of certain ions and nutrients may stimulate
hormone release—these stimuli are ___________ stimuli. For example,
the release of parathyroid hormone (PTH) by cells of the parathyroid
glands is prompted by decreasing blood calcium levels.
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In isolated cases, nerve fibers anyway, release and the target cells are said respond to
______________ stimuli. In example is the __________________ nervous system stimulation of
the entry number below the release norepinephrine epinephrine during periods of
stress.
The Major Endocrine Organs
The hypothalamus is part of the nervous
system, but it’s recognized as a major endocrine
organ because it produces several hormones.
Although the function of some hormone producing
glands it’s purely endocrine, the function of others
is mixed.
The _____________ gland is the size of a grape.
It hangs by a stalk from the inferior surface of the
______________________. It is protected by the _____________
bone. The gland has two funtional lobes:
 ______________________________—glandular tissue
 ______________________________—nervous tissue
There are _____ anterior pituitary hormones. ______
affect none-endocrine targets—the growth hormone
and prolactin. The remaining __________
stimulate other endocrine glands (tropic hormones: thyrotropic, adrenocorticotropic,
and two gonadotropic hormones). Tropic hormones stimulate their target organs,
which also endocrine glands, to secrete there hormones, which in turn exert their
effects on other body organs and tissues.
Characteristics of all anterior pituitary hormones inclide:
 ____________________
 __________________________________________
 ____________________________________________________
________________ _________________ (GH) is a general metabolic hormone. It’s major effects
are directed to growth _____________ muscles and _______ bones. It is a protein sparing
and anabolic hormone that causes of amino acids to be built into _____________. It also
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causes _________ to be broken down for a source of ___________ while it spares glucose,
helping to maintain a blood sugar homeostasis (Homeostatic Imbalance p. 305).
_________________ (PRL) stimulates and maintains ___________ production following
childbirth. It’s function in ___________ of unknown.
_____________________________ hormone (ACTH)
adrenal cortex.
regulates endocrine activity of the
_________________- ____________________ hormone (TSH) influences ___________and activity of
the thyroid.
_________________________ hormones regulate hormonal activity of the gonads.
___________________-____________________
hormone
(FSH)
stimulates
_____________
development in ______________. It also stimulates __________ development in __________.
__________________ hormone (LH) triggers ________________, causes ruptured follicles to
become the corpus luteum (progersterone and some estrogen). In males, it’s
simulates ___________________—referred to as interstitial cell-stimulating hormone
(ICSH) (Homeostaic Imbalance p. 305).
The anterior pituitary gland controls the activity of
so many other endocrine glands that it is often been
called the “master endocrine gland.” The removal or
destruction has a dramatic effect on the body. The
adrenal and thyroid glands atrophy. The release of
hormones is controlled by _________________ and
________________ hormones produced by the
____________________. The hypothalamus produces ____
hormones (oxytocin and antidiuretic hormone)
that are transported by _______________________ cells of
the posterior pituitrary. The posterior pituitary id not
strictly an endocrine glans, but does release hormones.
The posterior pituitary is more of a storage facilty until
a nerve impluse is receid from the hypothalmus.
The psoterior pituitary is not strictly an endocrine gland because it does not
make hormones, but does release hormones. ________________ is released in large
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amounts only during child birth, thus _____________________ contractions of the uterus
during labor. It also causes _______ ejection. Forms of oxytocin (i.e. Pitocin) are used to
induce labor. It is also used to stop postpartum bleeding.
Diuresis is urine production. __________________ hormone (ADH) can _____________
urine production. ADH causes the kidneys to reabsorb more water from the forming
urine; as a result, urine volume decreaes and blood volume increases. In large
amounts, it causes ___________________________________________ leading to increased blood
pressure, for this it is sometimes called ____________________. Drinking alcoholic
beverages inhibits ADH secretion and results in the output of large amounts of urine.
The dry mouth and intense thirst experienced “hangover” reflect this dehydrating
effect of alcohol (Homeostatic Imbalance . 307).
The thyroid gland is a hormone-producing gland that is familiar to most people
primarily because many ibese individuals blame their overweight condition on their
glands. The effect of the thyroid hormones on body weighr is not as great as many
believe it to be. The thyroid is found at the base of the ____________, just inferior to the
Adam’s apple. It consists of ____ lobes and a connecting
isthmus (or central mass). The thyroid produces ____
hormones:
 __________________________
 __________________________
The thyroid gland is composedc of hollow
structures called follicles, which store sticky colloidal
material.
Thyroid hormone is often referred to as the
body’s major ________________ hormone. It is composed of
___ active ___________-containing hormones:
 ________________ (T4)—secreted by thyroid follicles
 _________________________(T3)—conversion of T4 at target
tissues
Thyroid hormone controls the rate at which glucose is “burned,” or oxidized, and
converted to body heat and chemical energy. All body cells are a target (Homeostatic
Imbalance p. 309).
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Calcitonin, also called thyrocalcitonin, _______________ blood calcium levels by
causing its deposition on bone. It is ____________________ to parathyroid hormone (PTH).
It is produced by c (parafollicular) cells found in the connective tissue between the
follicles. It is released directly into the blood in repsonse to increasing levels of blood
calcium.
_________________________ glands are tiny masses of glandular tissue most often
found on the _______________ surface of the thyroid. There are a totalof ____ glands,
usually found two on each lobe of the thyroid. The parathyroid secretes PTH which is
the most important regulator of calcium ion homeostasis of te=he blood. PTH is
repsonsible for:
 ________________________________________________________________________
 ________________________________________________________________________
 ________________________________________________________________________
Adrenal Glands
The adrenal glands are ____ bean-shaped glands that curve over the top of the
_______________. Although the adrenal glands look like a single organ, it is structually
and functionally _____ endocrine glands in one:
 _______________—outer glandular region in three layers
 _______________—inner neural tissue region
The adrenal cortex produces ____ major groups of steroid horones collectvely called
corticosteroids:
1. _____________________________
2. _____________________________
3. _____________________________
Mineralcorticoid (mainly _______________) is produced in the ____________ adrenal
cortex. It regulates ____________ (sodium and potasiium ions specifically) content in the
blood, __________, and ___________________ balance. Their target organ is the kidney
tubules that selectively reabsorb the minerals or let them be flushed out with urine.
When blood levels of aldosterone rise, the kidney tubule cells reclaim increasing
amounts of Na2+ and secrete more K+ into the urine. When sodium is reabsorbed,
water follows. Release of aldosterone is stimulated by humoral factors (too few
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sodium ions, too many potassium ions). Production is stimulated by __________ and
angiotensin II. Production is inhibited by atrial natriuretic peptide.
Glucocorticoids (including _______________ and _______________) are produced in the
__________ layer of the adrenal cortex. Gluccocorticoids promote normal cell
_____________ and help the body resist __________-__________ _______________ by increasing
blood glucose levels. Due to their anti-inflammatory properties, gluccocorticoids are
often prescribed as drugs to supress inflammation for patients with rhematoid
arthritis. They are released in response toincreased blood levels of ___________.
Regardless of one’s gender, both male and female _______ ________________ are
produced by the adrenal cortex throughout life in relatively small amounts. Although
the bluk of sex hormones are prouced by the adrenal cortex layer are _____________
(male sex hormones), some ______________ (female sex hormones) are also formed
(Homeostatic Imbalance p. 311).
The adrenal medulla, like the posterior pituitary, develops from nervous tissue.
When the medulla is stmulated by the sympathetic nervous system neruons, its cells
will release ___ similar hormones (catecholamines) into the bloodstream:
 ______________________ (adrenaline)
 _______________________ (noradrenaline)
These hormones prepare the body to deal with _________-________ stress (Homeostatic
Imbalance p. 313-14). Catecholamines increase:
 ____________________________
 ____________________________
 ____________________________
 ____________________________
Pancreatic Islets
The ____________ is loocated in close proximity to the stomach, and is a _________
gland. The islets of the pancreas produce hormones. Two important hormones
produced by the islet cells are:
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 _______________—allows gluclose to cross plasma membranes into cells from beta
cells of the islets (hypoglycemic hormone), it targets all body cells.
 _______________—allows glucose to enter the blood from alpha cells
(hyperglycemic hormone, along with gluccocorticoids, and epinephrine), its
main target is the liver, causing it to break down stored glycogen to glucose.
These hormones are antagonists that maintain blood sugar homeostasis
(Homesostatic Imbalance p. 315).
Pineal Gland
The pineal gland is found in the __________ ventricle of the brain. It secretes
___________________, which is important for making one drowsy at night. It helps
establish the body’s _________ and ___________ cycles—found to secrete more melatonin
at night, and much less during the day. It may have other as-yet-unsubstantiated
functions.
Thymus Gland
The thymus gland is located _____________ to the ___________. It is largest in
___________ and _________________, and decreased in size throughout adulthood. It
produces ______________, which is important for maturing some types of ___________
____________ _________. It is important in developing the ______________ system.
Gonads
The males and female gonads produces sex hormones that are identical to those
produced by the adrenal cortex cells. The femae gonads, or ___________, are paired,
almond-sized organs located in the pelvic cavity. Besides producing female sex cells
(ova), the ovaries produce ____ groups of steroid hormones:
 __________________
 __________________
The ovaries do not really begin to function until puberty, when the nanterior
pituitary gonadotropic hormones stimulate them into activity.
Estrogens (primarily esterone) is produced by _____________ follicles or the
_____________, stimulates the development of _______________ female characteristics
(growth and maturation of the reproductive organs and the appearance of hair in th
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epubic and axillary regions). Estrogens work with progesterone to prepare the uterus
to receive a _________________ egg (producing cyclic changes in the uterine lining—
menstrual cycle). Estrogens also help ________________ pregnancy, and prepares the
breasts to produce ___________ (lactation).
Progesterone quiets the muscles of the uterus during pregnancy so the
implanted embryo will not be aborted. It is alsoproduced by the corpus luteum.
The paired oval testes of the male are suspended in a sac, the scrotum, outside
the pelvic cavity. In addition t making the male sex cells, sperm, the testes also
produce male sex hormones , or ______________, of which, ____________________ is the most
importnant. Testosterone is made by ______________________ cells of the testes. It is
responsible for adult male secondary characteristics (growth of facial hair,
developmennt of heavy bones and muscles, lowering of the voice, and stimulates
male sex drive). It promotes growth and maturation of male reproductive system. It
is required for sperm cell production.
Placenta
The placenta is a remarkable oran formed temporatily in the uterus of pregnant
women. In addition to its roles as the repiratory, excretory, and nutrition-delivery
systems for the fetus, it also produces hormones that maintain the _________________.
During very early pregnancy, a hormone callled human chorionic gonadotropic (hCG)
is produced by the developing embryo and then by the fetal part of the placenta. hCG
stimulates the corpus luteum of the ovary to continue to produce estrogen and
progesterone so that the lining of the uterus is not sloughed off in menses.
Developmental Aspects p. 323
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