Lesson 1
The Endocrine System
Why is the endocrine system important during the teen years?
The endocrine system is especially important during the teen
years because one of its main functions is to regulate growth
and development.
Lesson 1
Lesson Objectives
In this lesson, you’ll learn to:
Identify the glands of the endocrine system and explain the
function of each.
Examine the effects of health behaviors on the endocrine
system.
Appraise the significance of body changes occurring during
adolescence.
Lesson 1
Structure of the Endocrine System
The Endocrine System
The endocrine system consists of
a network of endocrine glands
located throughout the body.
Hormones are secreted by the
endocrine glands and then carried
to their destinations in the body
by the blood.
Hormones produced during
puberty trigger physical changes
in the body.
Lesson 1
Structure of the Endocrine System
Some Glands of the Endocrine System
Thyroid gland
Parathyroid glands
Hypothalamus
Pineal Gland
Testes and Ovaries
Thymus Gland
Pancreas
Lesson 1
Structure of the Endocrine System
Pituitary Gland
The pituitary gland is known as the master gland. It has three
sections, or lobes—anterior, intermediate, and posterior.
Lesson 1
Structure of the Endocrine System
Lobes of the Pituitary Gland
Anterior
Intermediate
Posterior
The anterior, or front, lobe of the pituitary gland
produces six hormones.
These hormones include somatotropic, or growth,
hormone, thyroid stimulating hormone, and
adrenocorticotropic hormone.
Follicle-stimulating hormone (FSH) and luteinizing
hormone (LH) control the growth, development,
and functions of the gonads.
Lesson 1
Structure of the Endocrine System
Adrenal Glands
The adrenal glands each have two parts.
Adrenal Cortex
Adrenal Medulla
The adrenal cortex secretes a hormone
that inhibits the amount of sodium
excreted in urine and serves to
maintain blood volume and pressure.
It also secretes hormones that aid the
metabolism of fats, proteins, and
carbohydrates.
Lesson 1
Problems of the Endocrine System
Serious Problems
Diabetes Mellitus
Graves’ Disease
Cushing’s Disease
Goiter
Growth Disorders
Lesson 1
Problems of the Endocrine System
Diabetes Mellitus
Diabetes mellitus is a disorder in which the pancreas produces
too little or no insulin, resulting in high blood glucose levels.
Symptoms include fatigue, weight loss, thirst, and frequent
urination.
Lesson 1
Problems of the Endocrine System
Graves’ Disease
Graves’ disease, also called hyperthyroidism, is a disorder in
which an overactive and enlarged thyroid gland produces
excessive amounts of thyroxine.
Symptoms include nervousness, weight loss, increased thirst,
rapid heartbeat, and intolerance for heat.
Low thyroxine production, called hypothyroidism, causes
fatigue, dry skin, weight gain, constipation, and sensitivity to
cold.
Lesson 1
Problems of the Endocrine System
Cushing’s Disease
Cushing’s disease results from the overproduction of adrenal
hormones.
Symptoms include round face, humped upper back, thin and
easily bruised skin, and fragile bones.
Lesson 1
Problems of the Endocrine System
Goiter
Goiter, an enlargement of the thyroid gland, is caused mainly
by a lack of iodine in the diet.
Since the introduction of iodized salt, goiters have become rare
in the United States.
Lesson 1
Problems of the Endocrine System
Growth Disorders
Growth disorders are caused by abnormal amounts of growth
hormone.
With early diagnosis and proper treatment, a child with a
growth disorder can reach a normal height.
Lesson 1
Problems of the Endocrine System
Care of the Endocrine System
Eat nutritious meals,
get enough sleep, and
avoid stress.
Get medical tests done
by health care
professionals to
determine whether
your endocrine
function is normal.
Lesson 1
Quick Review
Choose the appropriate option.
Q. The ovaries and testes are also
known by the name _________.
1. gonads
2. pituitary gland
3. goiter
4. adrenal cortex
Lesson 1
Quick Review - Answer
A. The ovaries and testes are also known by the name gonads.
Click Next to attempt another question.
Lesson 1
Quick Review
Provide a short answer to the question given below.
Q. What is an endocrine gland?
Click Next to view the answer.
Lesson 1
A.
Quick Review - Answer
An endocrine gland is a ductless, or tubeless, organ or
group of cells that secretes hormones directly into the
bloodstream.
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Lesson 1
Quick Review
Provide a short answer to the question given below.
Q. What are the two parts of the adrenal glands, and what do
they do?
Click Next to view the answer.
Lesson 1
A.
Quick Review - Answer
The two parts of the adrenal glands are:
Adrenal cortex: It secretes a hormone that inhibits
the amount of sodium excreted in urine and serves to
maintain blood volume and pressure.
Adrenal medulla: It secretes the hormones
epinephrine (also called adrenaline) and
norepinephrine.
Click Next to attempt another question.
Lesson 1
Quick Review
Analyze the following situation.
Which endocrine glands become more active during puberty?
Name the hormones these glands produce, and appraise the
significance of changes occurring during adolescence that they
cause.
Lesson 1
Quick Review - Answer
A. Correct! The ovaries and testes are also known by the name
gonads.
Click Next to attempt another question.
Lesson 1
Quick Review
You have answered the question incorrectly. Go back to try again,
or click Next to view the correct answer.
Lesson 1
Structure of the Endocrine System
Lobes of the Pituitary Gland
Anterior
Intermediate
Posterior
The intermediate, or middle, lobe of the pituitary
secretes melanocyte-stimulating hormone (MSH),
which controls the darkening of the skin by
stimulating skin pigments.
Lesson 1
Structure of the Endocrine System
Lobes of the Pituitary Gland
Anterior
Intermediate
Posterior
The posterior, or rear, lobe of the pituitary gland
secretes antidiuretic hormone (ADH), which
regulates the balance of water in the body.
ADH also produces oxytocin, which stimulates
uterine contractions during the birth of a baby.
Lesson 1
Structure of the Endocrine System
Lobes of the Pituitary Gland
Anterior
Intermediate
Posterior
The anterior, or front, lobe of the pituitary gland
produces six hormones.
These hormones include
somatotropic,
or growth,
A gonad
is
hormone, thyroid
stimulating
another
name hormone, and
adrenocorticotropic
hormone.
for the
ovary
and testes.
Follicle-stimulating hormone (FSH) and luteinizing
hormone (LH) control the growth, development,
and functions of the gonads.
Lesson 1
Structure of the Endocrine System
The Endocrine System
The endocrine system consists of
a network of endocrine glands
located throughout the body.
Hormones are An
secreted
by the
endocrine
endocrinegland
glands
then carried
is and
a ductless,
or
to their destinations
in theorbody
tubeless, organ
by the blood.
groups of cells that
secretes hormones
Hormonesdirectly
produced
intoduring
the
puberty trigger
physical changes
bloodstream.
in the body.
Lesson 1
Structure of the Endocrine System
The Endocrine System
The endocrine system consists of
a network of endocrine glands
located throughout the body.
Hormones are secreted by the
A hormone
is a
endocrine glands and
then carried
chemical
substance
to their destinations
in the
body
by the blood. that is produced in
glands and helps
Hormones produced
during
regulate
many of your
puberty triggerbody’s
physical
changes
functions.
in the body.
Lesson 1
Structure of the Endocrine System
Pituitary Gland
The pituitary gland is known as the master gland. It has three
sections, or lobes—anterior, intermediate, and posterior.
The pituitary
gland regulates and
controls the
activities of all of
the other endocrine
glands.
Lesson 1
Structure of the Endocrine System
Adrenal Glands
The adrenal glands each have two parts.
Adrenal Cortex
Adrenal Medulla
The adrenal
adrenal
gland is aThe
gland
that cortex secretes a hormone
helps the that
bodyinhibits the amount of sodium
excreted
recover from
stressin urine and serves to
maintain
blood volume and pressure.
and respond
to
emergencies.
It also secretes hormones that aid the
metabolism of fats, proteins, and
carbohydrates.
Lesson 1
Structure of the Endocrine System
Adrenal Glands
The adrenal glands each have two parts.
Adrenal Cortex
Adrenal Medulla
The adrenal
gland is aThe
gland
that medulla is controlled by
adrenal
helps thethe
body
hypothalamus and the autonomic
recover from
stress
nervous
system.
and respond to
It secretes the hormones epinephrine
emergencies.
(also called adrenaline) and
norepinephrine.
Lesson 1
Structure of the Endocrine System
Adrenal Glands
The adrenal glands each have two parts.
Adrenal Cortex
Adrenal Medulla
The adrenal medulla is controlled by
the hypothalamus and the autonomic
nervous system.
It secretes the hormones epinephrine
(also called adrenaline) and
norepinephrine.
Lesson 1
Structure of the Endocrine System
Some Glands of the Endocrine System
Thyroid gland
Parathyroid glands
The thyroid
Hypothalamus
gland produces
hormones
that
Pineal
Gland
regulate metabolism,
Testes
andheat,
Ovaries
body
and bone
growth.
Thymus Gland
Pancreas
Lesson 1
Structure of the Endocrine System
Some Glands of the Endocrine System
Thyroid gland
Parathyroid glands
Hypothalamus
The parathyroid
Pineal Gland
gland produces a
hormone
that
Testes
and Ovaries
regulates the body’s
Thymus
Gland
calcium
and
phosphorous balance.
Pancreas
Lesson 1
Structure of the Endocrine System
Some Glands of the Endocrine System
Thyroid gland
Parathyroid glands
Hypothalamus
Pineal Gland
The pancreas
is a gland that
Testes and Ovaries
serves both the
Thymus Gland digestive and the
endocrine systems.
Pancreas