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Introduction
Hormones
Functions
Table’s 16-7

The endocrine and nervous are
both communicators of the body.
The endocrine is a slow
communicator while the nervous
system is a fast communicator.
The nervous system collects and
processes information, analyzes
it, and generates coordinated
output to control complex
behaviors. The nervous system Endocrine
system
also is partly responsible for
(21)
homeostasis. It works in
conjunction with the endocrine
system by employing nerve
impulses and by responding
rapidly to stimuli to adjust body
processes. (2)

Facial
Skeleton
(21)
Overall function regulation of effectors to maintain
homeostasis
Control by regulatory
feedbacks loops Yes(endocrine reflexes)
Effector tissues endocrine effectors virtually all tissues
Effector cells target cells (3)

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* Organic chemical substances secreted by ductless
glands (or endocrine glands) and are released into
the blood stream for onward transportation to their
target organs.
* Regulate a variety of body functions.
-The way the body uses food growth
-Sex and reproduction the regulation of the
composition of the blood
-The body’s reaction to emergencies and the control
of hormones themselves(4)

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* Molecules manufactured by the endocrine cells
from cholesterol
* Derived from a common molecule, being
characterized by a chemical group at the core
of each molecule
* Ex: Cortisol. Aldosterone, estrogen,
progesterone, and (6)
*

* Do not enter the cell but bind to plasma
membrane receptors, generating a chemical
signal (second messenger) inside the target
cell.
* Five different second messenger chemicals,
including cyclic AMP have been identified.
Second messengers activate other intracellular
chemicals to produce the target cell
response.(7)
*

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*
is any member of a group of lipid
compounds that are derived
enzymatically from fatty acids and
have important functions in the
animal body. Every prostaglandin
contains 20 carbon atoms,
including a 5-carbon ring.(7)

* is an endocrine gland about the
size of a pea and weighing 0.5
*
gramsin humans. It is not a part of
the brain. It is a protrusion off the
bottom of the hypothalamus at
the base of the brain, and rests in
a small, bony cavity covered by a
dural fold. The pituitary is
functionally connected to the
hypothalamus by the median
eminence via a small tube called
the infundibular stem. The
pituitary fossa, in which the
pituitary gland sits, is situated in
the sphenoid bone in the middle
cranial fossa at the base of the
brain. The pituitary gland secretes
nine hormones that regulate
homeostasis(8)
(9)

* is a small endocrine gland in the vertebrate
brain. It produces the serotonin derivative
melatonin, a hormone that affects the
modulation of wake/sleep patterns and
seasonal functions. (10)
*
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* The thyroid gland is found in the neck, below the
thyroid cartilage (which forms the laryngeal
prominence, or "Adam's apple"). The isthmus (the
bridge between the two lobes of the thyroid) is
located inferior to the cricoid cartilage.
*
* The thyroid gland controls how quickly the body
uses energy, makes proteins, and controls how
sensitive the body is to other hormones. It
participates in these processes by producing thyroid
hormones, the principal ones being triiodothyronine
(T3) and thyroxine which can sometimes be referred
to as tetraiodothyronine (T4). These hormones
regulate the rate of metabolism and affect the
growth and rate of function of many other systems
in the body. T3 and T4 are synthesized from both
iodine and tyrosine. The thyroid also produces
calcitonin, which plays a role in calcium
homeostasis.(12)
*

* The parathyroid glands are small endocrine
glands in the neck that produce parathyroid
hormone. Humans usually have four
parathyroid glands, which are usually located
on the rear surface of the thyroid gland, or, in
rare cases, within the thyroid gland itself or in
the chest. Parathyroid glands control the
amount of calcium in the blood and within the
(13)
bones.
(14)
*

* the adrenal glands are endocrine glands that sit at
the top of the kidneys; in humans, the right adrenal
gland is triangular shaped, while the left adrenal
gland is semilunar shaped. They are chiefly
responsible for releasing hormones in response to
stress through the synthesis of corticosteroids such
as cortisol and catecholamines such as epinephrine
and norepinephrine. They also produce androgens.
The adrenal glands affect kidney function through
the secretion of aldosterone, a hormone involved in
regulating the osmolarity of blood plasma. (15)
*

Functions
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* Triangular-shaped glands located on top of the
kidneys. They produce hormones such as
estrogen, progesterone, steroids, cortisol, and
cortisone, and chemicals such as adrenalin
(epinephrine), norepinephrine, and dopamine. (16)
*

* Throughout the pancreas are clusters of cells
called the islets of Langerhans. Islets are made
up of several types of cells, including beta cells
that make insulin.
*

* The testes are two egg-shaped male
reproductive organs located in the scrotum.
They produce sperm and the male hormone,
testosterone.
*

* The placenta is a structure that develops in
your uterus during pregnancy. The placenta
provides oxygen and nutrients to your growing
baby and removes waste products from your
baby's blood. It attaches to the wall of your
uterus, and your baby's umbilical cord arises
from it. In most pregnancies, the placenta
attaches at the top or side of the uterus.
*

* The thymus is a small organ in your upper
chest, under your breastbone. Before birth and
during childhood, the thymus helps the body
make a type of white blood cell. These cells
help protect you from infections.
*

* The gastrointestinal mucosa forms a barrier
between the body and a lumenal environment
which not only contains nutrients, but is laden
with potentially hostile microorganisms and
toxins. The challenge is to allow efficient
transport of nutrients across the epithelium
while rigorously excluding passage of harmful
molecules and organisms into the animal. The
exclusionary properties of the gastric and
intestinal mucosa are referred to as the
gastrointestinal barrier.
*

* The heart is a muscular organ about the size of
a fist, located just behind and slightly left of
the breastbone. The heart pumps blood
through the network of arteries and veins
called the cardiovascular system. The heart
moves the hormones throughout the body.
*

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Hormone Source Targets Principal Action
Growth hormone-releasing hormone Hypothalamus Adenohypophysis Stimulates secretion of growth hormone
GRH (somatotrophs)
Growth hormone- inhibiting hormone Hypothalamus Adenohypophysis Inhibits secretion of growth hormone
GIH, or somatostatin (somatotrophs)
Corticoptropin- releasing hormone CRH Hypothalamus Adenohypophysis Stimulates release of adrenocorticotrophic hormone ACTH
(corticotrophs)
Thyrotropin-releasing hormone TRH Hypothalamus Adenohypophysis Stimulates release of thyroid-stimulating TSH
(thyrotrophs)
Gonadotropin- releasing hormone Hypothalamus Adenohypophysis Stimulates release of gonadotropins (FSH and LH)
GNRH (gonadotrophs)
Prolactin-releasing hormone PRH Hypothalamus Adenohypophysis Stimulates secretion of prolactin
(corticotrophs)
Prolactin- inhibiting hormone PIH Hypothalamus Adenohypophysis Inhibits secretion of prolactin
(corticotrophs)
Growth hormone GH (somatotrophs Adenohypophysis General Promotes growth by stimulating protein anabolism
[STH]) (somatotrophs)
Prolactin PRL (lactogenic hormone) Adenohypophysis Mammary glands Promotes milk secretion
(lactotrophs) (alveolar secretory
cells)
Thyroid-stimulating hormone TSH Adenohypophysis Thyroid gland Stimulates development and secretion in the thyroid gland
(thyrotrophs)
Adenocorticotrophic hormone ACTH Adenohypophysis Adrenal cortex Promotes development and secretion in the adrenal cortex
(corticotrophs)
Follicle-stimulating hormone FSH Adenohypophysis Gonads (primary Female: promotes development of ovarian follicle; stimulates
(gonadotrophs) sex organs) estrogen secretion
Male: promotes development of testis; stimulates sperm production
Luteinizing hormone LH Adenohypophysis Gonads Female: triggers ovulation; promotes development of corpus luteum
(gonadotrophs) Male: simulates production of testosterone
Antidiuretic hormone ADH Neurohypophysis Kidney Promotes water retention by kidney tubules
Oxytocin OT Neurohypophysis Uterus and Stimulates uterine contractions; stimulates ejection of milk into
mammary gland mammary glands

Hormone Source Targets Principal Action
Triiodothyronine (T3) Thyroid gland (follicular cells) General Increase rate of metabolism
Tetaiodothyronine (T4) Thyroid gland (follicular cells) General Increases rate of metabolism (usually converted to T3 first)
or thyroxine
Calcitonin CT Thyroid gland (parafollicular cells) Bone tissue Increases calcium storage in bone; lowering blood Ca++ levels
Parathyroid hormone Parathyroid glands Bone tissue and kidney Increases removal from storage in bone and produces the
PTH or parathromone active form of vitamin D in the kidneys, increasing absorption
of calcium by intestines and increasing blood Ca++ levels
Aldosterone Adrenal cortex (zona glomerlulosa) Kidney Stimulates kidney tubules to conserve sodium, which, in turn,
triggers, the release of ADH and the resulting conservation of
water by the kidney
Cortisol (hydrocortisone) Adrenal cortex (zona fasciculata) General Influences metabolism of food molecules; in large amounts, it
has an anti-inflammatory effect
Adrenal androgens Adrenal cortex (zona reticularis) Sex organs, other Exact role uncertain, but may support sexual function
effectors
Adrenal estrogens Adrenal cortex (zona reticularis) Sex organs Thought to be physiologically insignificant
Epinephrine Adrenal medulla Sympathetic effectors Enhances and prolongs the effects of the sympathetic division
(adrenaline) of the autonomic nervous system
Norepinephrine Adrenal medulla Sympathetic effectors Enhances and prolongs the effects of the sympathetic division
of the autonomic nervous system
Glucagon Pancreatic islets (alpha [a] cells or General Promotes movement of glucose from storage and into the
A cells) blood
Insulin Pancreatic islets (beta [b] cells or B General Promotes movement of glucose out of the blood and into
cells) cells
Somatostatin Pancreatic islets (delta [d] cells or D Pancreatic cells and Can have general effects in the body, but primary role seems
cells) other effectors to be regulation of secretion of other pancreatic hormones
Pancreatic polypeptide Pancreatic islets (pancreatic Intestinal cells and Exact function uncertain, but seems to influence absorption
polypeptide [PP] of F cells) other effectors in the digestive tract

* Group didn’t do all their citations….
* -megan