Download Chapter 13 Endocrine System

Chapter 13
Endocrine System
Chapter Objectives
Upon completion of this chapter the participant will be able to:
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7.
8.
Define hormones.
Define homeostasis.
List the glands of the endocrine system.
Define what is meant by the “master gland”.
Discuss the function of each of the endocrine glands.
Label a diagram of the endocrine glands.
Analyze, pronounce and define the terms related to the endocrine system.
Successfully complete the exercises at the end of the chapter.
The endocrine system is a series of glands that secrete chemicals called hormones
directly into the blood. The blood then carries the hormone to the particular part of the
body where it will have its action. One of the prime functions of the endocrine system is
the maintenance of the body in a state of homeostasis. Homeostasis is a state of
balance that the body must attain if all systems are to function to their optimum.
Structures of the Endocrine System
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Pituitary Gland (pituit/o): The master gland that is located at the base of the
brain. It consists of two lobes, the anterior and the posterior. This gland is referred
to as the master gland because it secretes hormones that affect how the other
endocrine glands function.
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Thyroid Gland (thyr/o, thyroid/o): Butterfly shaped gland found on either side of
the larynx in the neck. It secretes thyroxine and calcitonin which affect
metabolism in the body and the regulation of calcium levels in the blood.

Parathyroid Glands: There are four parathyroid glands, each of which is about the
size of a grain of rice. These glands are located on the posterior side of the thyroid
gland (para-: near, upon). The function of the hormone released from this gland is
to work with calcitonin to control the blood levels of calcium.

Adrenal Gland (adren/o, adrenal/o): Two small glands which sit like a hat on the
top of each kidney. Each adrenal gland has two parts; a cortex (cortic/o) which is
the outer portion and a medulla (medull/o) which is the inner portion. This gland
releases a number of hormones that are responsible for: regulating water levels in
the body, affecting the body’s response to inflammation, nutrient absorption and
development of male sex characteristics.

Pancreas (pancreat/o): Located behind the stomach this gland is involved with
digestion and only part of the gland has an endocrine function. Part of the gland is
the islets of langerhans which secrete insulin that is involved with the breakdown
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of sugars. When there is not enough insulin being produced you develop a
condition called diabetes mellitus.

Thymus Gland (thym/o): A gland located in the anterior portion of the thoracic
(chest) cavity. It functions to bring about the maturing of white blood cells which
help to fight infections in the body.
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Pineal Gland (pineal/o) This gland is located in the central part of the brain and
secretes hormones that are responsible for the normal sleep/wake cycle and a
hormone that assists with stimulating smooth muscle action.

Reproductive Glands: Gonads (gonad/o): These glands differ in men and
women. In females the reproductive glands are the ovaries and they release
estrogen and progesterone which are necessary for the development of eggs and
the fetus when the egg is fertilized. In men the testes are the reproductive gland
and they secrete testosterone.
Pineal Gland
Pituitary Gland
Thyroid Gland
Parathyroid Gland
Thymus Gland
Pancreasl Gland
Islets of Langerhans
Adrenal Gland
Ovary in females
Testes in males
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Endocrine Glands contained in the body and their function …
Gland
Anterior
Pituitary
Posterior
Pituitary
Thyroid
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Hormone
Function
somatotrophin (growth
hormone)
Stimulates growth of body cells.
thyrotrophin (thyroid
stimulating hormone
TSH)
Stimulates the thyroid gland to
produce T3 and T4
corticotrophin
(adrenocorticotrophic
hormone ACTH)
Stimulates the adrenal cortex to
release cortisol and aldosterone.
gonadotrophin (follicle
stimulating hormone
FSH)
Development of the ovaries and
testes: promotes monthly growth of the
egg in females and sperm production
in males.
gonadotrophin
(luteinizing hormone
LH)
Triggers ovulation in women and
regulates the secretion of sex hormone
in men.
prolactin
Stimulates production of milk by the
mammary gland
melanocytestimulating hormone
(MSH)
produces melanin for skin
pigmentation
antidiuretic hormone
(ADH)
Regulates the retention of water in the
body.
oxytocin
Regulates the flow of milk in mammary
glands and stimulates uterine
contraction during childbirth.
thyroxine (T4) &
triiodothyronine (T3)
Increase metabolic rate and stimulates
growth
calcitonin
Regulates blood calcium levels
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Gland
Hormone
Function
Parathyroid
parathyroid hormone
(PTH)
Contributes to the regulation of blood
calcium and phosphorus levels.
Adrenal Cortex
glucocorticoid
hormone
Production of antibodies, involved in
the body’s stress response and the
metabolism of fats, carbohydrates and
proteins.
mineralocorticoid
hormones
(aldosterone)
Regulates sodium and potassium
levels
sex hormones
(estrogen and
testosterone)
Development of the secondary sex
characteristics in males and females.
Adrenal Medulla
epinephrine and
norepinephrine
Helps the body respond to stress
Pineal Gland
melatonin
Involved in the sleep/wake cycle.
Pancreas
insulin, glucagon
Insulin converts glucose to glycogen.
Glucagon converts glycogen to
glucose.
Word parts for the Endocrine System
Roots
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acr/o
aden/o
adren/o, adrenal/o
andr/o
calc/o, calc/i
cortic/o
crin/o
estr/o
gluc/o, glyc/o
glycogen/o
gonad/o
gynec/o
home/o
insulin/o
kal/o
ket/o
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extremities
gland
adrenal gland
male
calcium
outer region
secrete
female
sugar
glycogen
gonad
female
same
insulin
potassium
ketones
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lact/o, lact/i, galact/o
lactat/o
lute/o
medull/o
melan/o
natr/o
pancreat/o
parathyroid/o
pineal/o
pituit/o
ren/o, nephr/o
somat/o
thym/o
thyr/o, thyroid/o
 toxic/o
 troph/o
 ure/o
milk
secrete milk
yellow
inner section
black, dark
sodium
pancreas
parathyroid gland
pineal gland
pituitary
kidney
body
thymus
thyroid gland
poison
relating to nourishment, development, growth
urea
Suffixes



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
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-assay
-crine
-dipsia
-emia
-ism
-ma
-physis
-tropic, -trophy
-uria
analysis
to secrete
thirst
blood
state of
tumor
to grow
pertaining to nourishment
urine
Prefixes
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adantieuoxypanparapoly-
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toward
against
well, good, normal
sharp, quick
all, entire
near
many
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Term Analysis and Definition
Word Part
Term
acr/o
acromegaly
acr = extremity
-megaly =
enlargement
Enlargement of the extremities
aden/o
adenoma
aden = gland
-oma = tumor
Tumor of a gland
adrenal/o,
adren/o
adrenalectomy
adrenal = adrenal
gland
-ectomy =
surgical removal
Surgical removal of the adrenal
gland
adrenocortical
-al = pertaining to
cortic = cortex
Pertaining to the cortex of the
adrenal gland
hypercalcemia
hyper =
excessive
calc = calcium
emia = blood
Excessive calcium in the blood
hypocalcemia
hypo = deficient
Deficiency of calcium in the
blood
endocrinology
endo = within
crin = to secrete
-logy = study of
Study of the diagnosis and
treatment of endocrine
disorders.
endocrinologist
-logist
Specialist in endocrinology
estr/o
estrogen
estr = female
-gen =producing
Female producing hormones
gluc/o
glyc/o
glucogenesis
gluc = sugar
-genesis =
production
Production of sugar
hyperglycemia
hyper =
excessive
glyc = sugar
-emia = blood
Excessive amounts of sugar in
the blood
hypoglycemia
hypo = deficiency
Deficiency of sugar in the
blood
glycolysis
-lysis =
Breakdown of sugar
calc/o
calc/i
crin/o
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Analysis
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Definition
Word Part
Term
Analysis
Definition
breakdown
glycogen/o
glycogenolysis
glycogen =
glycogen
-lysis =
breakdown
Breakdown of glycogen to
glucose
gonad/o
hypergonadism
hyper =
excessive
gonad = sex
glands
-ism = condition
Condition characterized by
excessive secretion of sex
hormones.
hypogonadism
hypo = deficiency
Condition characterized by
deficiency in secretion of sex
hormones.
gynecomastia
gynec = woman
mast = breast
-ia = condition
Abnormal enlargement of the
male breast, like that of the
female breast
gynecology
-logy = study of
Study of diseases that occur in
women
home/o
homeostasis
home = same
-stasis = stable,
controlling
Balanced state
insulin/o
hyperinsulinism
hyper =
excessive
insulin = insulin
-ism = condition
Condition where there is an
excess in secretion of insulin
hypoinsulinism
hypo = deficiency
Condition where there is a
deficiency in secretion of
insulin
hyperkalemia
hyper =
excessive
kal = potassium
-emia = blood
Excessive potassium in the
blood
hypokalemia
hypo = deficiency
Deficiency of potassium in the
blood
hypernatremia
hyper =
excessive
natr = sodium
Excessive sodium in the blood
gynec/o
kal/o
natr/o
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Word Part
Term
Analysis
Definition
-emia = blood
hyponatremia
hypo = deficiency
Deficiency of sodium in the
blood
parathyroid/o
Hyperparathyroidism
hyper =
excessive
parathyroid =
parathyroid gland
-ism = condition
Condition where there is an
excess in the secretion of
hormones of the parathyroid
gland.
pituitar/o
panhypopituitarism
pan = all
pituitar = pituitary
gland
hypo = deficiency
-ism = condition
Condition where there is a
deficiency in all the hormones
produced by the pituitary gland.
thyr/o,
thyroid/o
euthyroid
eu = normal,
good
-oid = resembling
thyr = thyroid
gland
Resembling a normal thyroid
gland
hyperthyroidism
hyper =
excessive
-ism = condition
Condition where there is
excessive secretion of the
hormones produced by the
thyroid gland.
thyroiditis
-itis =
inflammation
Inflammation of the thyroid
gland
thyrotomy
-tomy = surgical
incision
Surgical incision into the
thyroid gland
ure/o
antidiuretic
hormone
anti = against
ure = urea
-tic = pertaining to
Hormone that prevents the loss
of excessive amounts of urine
-assay
radioimmunoass
ay
radi = radioactive
immun = safe
-assay = analysis
Blood test to identify hormone
levels in the blood
to identify contents
-crine
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endocrine
-crine = to
secrete
endo = within
Secretions of endocrine gland
hormones directly into the
blood.
exocrine
ex = outside
Glands that secrete chemical
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Word Part
Term
Analysis
Definition
into ducts
-dipsia
polydipsia
poly = many
dipsia = thirst
Excessive thirst
-physis
adenohypophysis
-physis = to grow
aden = gland
hypo = below,
under
Another name for the anterior
pituitary gland
neurohypophysis
neuro = nerve
Another name for the posterior
pituitary gland
-trophic,
tropic
adrenocorticotrophic
adreno = adrenal
gland
cortic = cortex,
outer layer
-trophic =
nourishment
Pituitary hormone that
stimulates the adrenal cortex to
secrete its own hormones
oxy-
oxytocin
oxy = sharp,
quick
-tocin = labor
Pituitary hormone that
quickens childbirth
Abbreviations:
ADH
antidiuretic hormone
BMR
basal metabolic rate
IDDH
insulin dependent diabetes mellitus
NIDDM
non-insulin dependent diabetes mellitus
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