3. Defination
The Endocrine System is made of glands
and tissues that secrete hormones.
The Endocrine System is a set of glands
that regulates the activities of certain
organs by releasing their chemical
products into blood stream.
These glands have no ducts or openings
4. Controls many body functions
Exerts control by releasing special chemical
substances into the blood called hormones.
Hormones effects other endocrine glands or
body systems.
5. Glands of Endocrine System
Following glands are included in
endocrine system :
Pituitary Gland
Thyroid Gland
Parathyroid Gland
Thymus Gland
Adrenal Gland
Pancreas Gland
Pineal Gland
Gonad Gland
6.
7. Pituitary Gland
Located at the base of brain and
connected to the hypothalamus
Divided into interior and posterior lobes
Known as the master gland because of its
major influence in body’s activities
8.
9. Hormones of the Pituitary Gland
Divided into two lobes
Anterior pituitary lobe is larger and produces
seven hormones.
Posterior pituitary lobe is smaller and consist
primarily of nerve fibers and neuroglial cells.
10. Anterior pituitary
The anterior pituitary synthesizes and
secretes the following important
hormones under the influence of
hypothalamus
◦ Adrenocorticotropic hormone (ACTH)
◦ Thyrotropin or thyroid stimulating hormone
◦ Prolactin hormone
◦ Growth hormone
◦ Gonadotropin hormone
12. Thyroid and Parathyroid Glands
Thyroid Glands
Locted in the anterior part of neck
It is butterfly shape organ and is
composed of two con-like lobes or
wings
Secretes three hormones
Thyroxine
Triiodthyronine
Calcitonin
13. Thyroid and Parathyroid Glands
Parathyroid Glands
They are small endocrine glands in the neck
that produce parathyroid hormone.
Humans have four parathyroid glands, which
are located behind the thyroid gland.
Parathyroid glands control the amount of
calcium in the blood and within the bones
It serves a completely different role than the
thyroid gland.
14.
15. Thymus Gland
The thymus gland is both an endocrine
gland and lymphatic organ.
The thymus secretes a large number of
hormones
It is composed of two lobes and is
located in front of the heart and behind
the sternum.
Thymus is specialized organ in the
immune system.
16. Structure of thymus
Structure of the thymus can be divided
into two parts
Medulla
Peripheral cortex
The cortex and medulla play different
roles in the development ofT-cells.
17. Adrenal Glands
Adrenal glands are situated just above the
kidneys one on each side.
These are triangular shaped glands.
They are chiefly responsible for releasing
hormones which are extremely important
to neural functioning and to the ability of
the body to cope with stress.
18. Adrenal Glands
Two adrenal glands located at the top of
each kidney; each has two parts
Cortex – secretes 3 groups corticoids
• Mineralocorticoids
• Glucocorticoids
• Sex hormones
Medulla – secretes
• Epinephrine / adrenaline
• Nor – epinephrine / nor adrenaline
19. Pancreas Gland
Located behind stomach
Pancreas is a dual function gland i.e.
endocrine or exocrine gland
Function as :
• Exocrine gland
oSecretes pancreatic juices into small intestine to
become digestive juices
• Endocrine gland
oProduces insulin and diabetes.
20. Pineal Gland
Attached to the third ventricle of the
brain
Produces the hormone melatonin
• Amount of light effects the amount of
melatonin secreted
• Causes body temprature to drop
21. Gonad Gland
Gonads – sex organs
Ovaries – female sex organ
• Ova
• Estrogen and progesterone
Testes – male sex organ
• Sperm
• testosterone