1. Endocrine System Function
control systems,
maintain homeostasis:
a) control chemical and water balance in body
b) control growth and metabolism
c) control embryonic development and preparation
for nurturing a newborn
d) influence sexual behavior, stimulate growth and
maturation of the gonads
e) feedback to the nervous system

2. The Endocrine System
• Derives its name from
the fact that various
glands release
– Through special chemical
hormones directly into
substances released into
the blood called hormones
the blood, which in turn
– Hormones affect other
transports the
endocrine glands or body
hormones to target
systems, speeding up or
organs.
slowing down the activity of
• Controls many body
functions
these organs
Once used, hormones do not
remain in the blood, they are
changed in the liver and
excreted by the kidneys

3. Endocrine System
How does it work?
Basic Overview of the Feedback System
1) Nervous systems monitors environment
2) If aberrations are detected - nervous system
sends message to endocrine glands
3) Endocrine glands produce and secrete
hormones into blood
4) Hormones hit target organ
5) Target organ produces substance
6) Substance is picked up by receptors and
brain stops sending message to endocrine
glands

4. Response of the body to
Hormones
Affect long-term
changes such as
Growth rate
Puberty
Pregnancy
Slower
Often affect
many organ
systems at once
Defficiency or
excess produce
illnesses
It depends on the
speed of the
circulatory system

5. The Endocrine System
•
• Consists of several glands
located in various parts of
the body.
Pituitary gland: a small
gland attached the base of
the brain
•
“The Master Gland”
– Primary function is to
control other glands.
– Produces many
hormones.
– Secretion is controlled by
the hypothalamus in the
base of the brain.

6. The Pituitary Gland produces
• Antidiuretic hormone (ADH)
• Regulates the amount of
water reabsorbed in the
KIDNEYS
• Thyroid-stimulating hormone •
Acts on thyroid and make
(TSH)
it produce THYROXINE
• Growth hormone (GH)
• Follicle-stimulating hormone
(FSH)
• Luteinizing hormone (LH)
(T3 and T4)
*Affects the growth rate of
the body and the skeleton
in particular
* Regulates the development,
growth, pubertal maduration
and reproductive process of the
body in GIRLS
When it reaches the ovaries, it
makes one of the follicles start to
mature and to produce oestrogen
* Together with FSH induces
OVULATION

7. The Endocrine System
– TSH stimulates the
thyroid gland to
release its
hormones, thus ↑
metabolic rate
– Growth hormone
(GH)
∀ ↓ glucose usage
∀ ↑ consumption of
fats as an energy
source
– ACTH stimulates the
adrenal cortex to
release its hormones
– FSH & LH stimulates
maturation & release
of eggs from ovary.

10. Pituitary Gland
Disorders: To much growth
hormones (GH) in early
childhood can result in a
condition called gigantism. To
little GH can result in Pituitary
Dwarfism.
Robert
Wadlow

11. The Endocrine System
• The Thyroid Gland
– lies in the anterior neck
just below the larynyx.
– Two lobes, located on
either side of the
trachea, connected by a
narrow band of tissue
• It produces the thyroid
hormones:
– thyroxine (T4)
•
AA+ iodine
It controls our level of activity,
promotes normal skeletal growth
and normal development of the
brain
– triiodothyronine (T3)
• When stimulated (by
TSH or by cold), these
are released into the
circulatory system and ↑
the metabolic rate.

12. The Endocrine System
• Inadequate levels of
thyroid hormones =
a) hypothyroidism
b) hyperthyroidism
•
Symptoms:
– Facial bloating
– weakness
– cold intolerance
– lethargy
– altered mental status
– oily skin and hair
Signs and symptoms:
-insomnia,
fatigue
-tachycardia
-hypertension
-heat intolerance
-weight loss

13. The Endocrine
System
• Pancreas
– a key gland located in
the folds of the
duodenum
– has both endocrine
(ductless) and exocrine
functions
– secretes several key
digestive enzymes but
also hormones
• Islets of Langerhans
– specialized tissues in
which the endocrine
functions of the
pancreas occurs
– include 3 types of
cells:
• alpha (α )
• beta (β)
• delta (∂)
– each secretes an
important hormone.

14. The Endocrine System
• The rise of glucagon
• When blood glucose
stimulates the liver to
levels fall, α cells↑ the
* release glucose stores
amount of glucagon in the
(from glycogen and
blood .
additional storage
sites(fats))
* to manufacture glucose
(gluconeogenesis)
• HIGH level of sugar in the
blood

15. The Endocrine System
• When the level of sugar in
the blood is HIGH
• Beta Cells (β) release
insulin (antagonistic to
glucagon).
Delta Cells (∂) produce
somatostatin, which
inhibits both glucagon and
insulin.
• When Insulin reaches the
liver, it stimulates the liver
cells to take up glucose
and store it as
GLYCOGEN
• Insulin ↑ the rate at which
various body cells take up
glucose. Thus, insulin
lowers the blood glucose
level.

16. GLUCAGON
INSULIN
Encourages the burning of fats for
energy
Encourages the storage of fats/ burns
glucose for energy
Encourages the use of cholesterol,
slows down the cholesterol
production
Encourages the production of
cholesterol, to be stored
Promotes the kidneys to remove salts Slows down the kidneys, it stops
and fluids from bloodstream 
salts and fluids from leaving
Blood pressure DECREASES
INCREASES blood pressure
Happens some time after eating
Secreted after you eat
Encourages the breakdown of
smooth muscle over your vessels
to make room for blood to flow
Blood pressure DECREASES
Encourages the growth of smooth
muscle over your vessels less
room for blood to flow
Blood pressure INCREASES
There´s no easy way to increase the
production of GLUCAGON
Is increased by consuming
carbohydrates

17. DIABETES
Type 1
Type 2
Failure of the islets to produce
sufficient insulin
Reduced ability of the body
cells to use insulin
Less common
Common in over 40-year-old
people
Autoimmune/ inherited
Most common obesity
Juvenile onset
Adult onset
Insulin-dependent
Controlled by diet/doesn’t
require insulin

18. • Adrenal Glands
*2 small glands that sit atop both kidneys.
* Each has 2 divisions, each with different
functions.
1) the Adrenal Medulla secretes ADRENALINE
(closely related to the sympathetic component of the autonomic
nervous system).
Also called epinephrine, 1) increases blood pressure and heart rate when
the body experiences stress
2) supplies more oxygen to your brain and
muscles
3)constricts the vessels in your skin and
digestive system
4) tenses your muscles (to run away)
5) conversion of glycogen into glucose/fats to
fatty acids

20. The Endocrine System
2) The Adrenal Cortex secretes steroid hormones
(corticosteroids) synthesized from cholesterol
– gluticocorticoids: CORTISOL
-↑ the level of glucose in the blood/ controls the metabolism of
carbohydrates, lipids and proteins
– Released in response to stress, injury, or serious infection
– Mineralocorticoids:ALDOSTERONE
– work to regulate the concentration of potassium and
sodium in the body.

21. The Endocrine System
Reproductive organs
• Gonads and Ovaries:
– the endocrine glands associated with human reproduction.
– They produce a) GAMETES  Female ovaries produce
eggs and male gonads produce sperm
b) HORMONES
Testes:
Ovaries:
Controlled by pituitary
hormones FSH and LH, they
manufacture
• testosterone
promotes male growth
and masculinization
Under the control of LH and FSH
from the pituitary gland, they
manufacture
• estrogen
• protesterone
Prepare the uterus for the implantation
of the embryo

22. Where are these hormones
generated?
Thyroxine
Insulin
testosterone
Calcitonin
growth hormone
estrogen
progesterone
Epinephrine or Adrenaline
Glucagon

23. Which disease do you
think they suffer?

24. Performance- enhancing
hormones
ANABOLIC STEROIDS and
HUMAN GROWTH
HORMONE increases muscle
development and reduces body fat
Side effects: sterility, masculinization, liver and
kidney malfunction
ERYTHROPOIETIN
(EPO) stimulates production of
red blood cells more oxygen in sports
that require resistance
Side effects: risk of strokes and heart attacks