This document discusses the endocrine system and its glands. It begins by defining endocrinology and the endocrine system. The endocrine system maintains homeostasis, regulates growth and development, and controls reproduction. Hormones are chemical messengers released from glands into the bloodstream and target specific cells. The major glands discussed are the pituitary gland and thyroid gland. The pituitary gland is called the "master gland" as it regulates other glands by releasing hormones like growth hormone. Disorders of the pituitary can cause dwarfism or gigantism. The thyroid gland regulates metabolism through thyroxine production, and disorders can result in goiter, myxedema, or Graves' disease.

2. Endocrinal Glands
Endocrinology: The study of hormones,
the endocrine system, and their role in
the physiology of the body.
The Endocrine System: The body’s slow
chemical communication system; a set of
glands that secrete hormones into the
blood stream.

3. Endocrine system: Principal functions
 Maintenance of the internal environment in
the body (maintaining the optimum
biochemical environment).
 Integration and regulation of growth and
development.
 Control, maintenance and instigation of
sexual reproduction, and development and
nourishment of the newborn.

4. Hormones
A chemical released from living cells
that travels some distance to target
tissues to have a biological effect.
 Secreted in very small amounts.
 Transported, usually, in the blood.
 Target cells have specific receptors.

5. Major Endocrine Glands Location
 This system works in
conjunction with
different parts of the
nervous system.
 The whole system is thus
known as neuroendocrine
system.
 Figure shows the major
endocrine glands of the
body.

6. 1. Pituitary Gland
 Location: This gland is
situated within the cranium
just below the
hypothalamus.
 Functions: The pituitary
gland is divided into
anterior pituitary and
posterior pituitary. The
anterior pituitary is
directly connected with
hypothalamus, which
regulates its hormonal
secretions.

7. Why master gland
The pituitary gland secretes the
growth hormone and many other
hormones, which direct and regulate
the secretions of many other
endocrine glands found in our body.
This is why the pituitary gland is
known as the “master gland”.

8. Impact of the Functioning
 It regulates and controls the
other endocrine glands, and is
responsible for the regulation
of growth and other
associated physiological
activities.
 It secretes pitutrin and other
hormones. Under-activity of
the pituitary gland leads to
dwarfism. Deficiency during
the pre-pubertal stage can
give rise to midgets.

9. Impact of the Functioning

10. Impact of the Functioning
 Over activity during the growth period results in
gigantism.
 Over activity during adulthood results in a
condition called Acromegaly (overgrowth of
cartilage and joints)

11. 2. Thyroid Gland
 Location: This gland is located in the neck.
 Function: It produces thyroxin that influences
the body’s metabolic rate. Optimum amount
of thyroxin is secreted and regulated by an
anterior pituitary hormone, the Thyroid
Stimulating Hormone (TSH).

12. Impact of the Functioning
The steady secretion of TSH hormone
maintains the production of energy,
consumption of oxygen and elimination
of wastes in body cells.
The thyroid glands produce thyroxin or
iodine and they are responsible for the
rate of living activity. They influence
metabolic rate, growth and
development.

13. Impact of the Functioning
Thyroid deficiency in infancy
leads to cretinism or
feeblemindedness.
Thyroxin of poor quality
leads to a condition known as
goitre or enlargement of the
gland.

14. Impact of the Functioning
 Thyroid deficiency in adulthood
leads to a condition referred to as
myxedema which is characterized
by overweight and general
sluggishness.
 Thyroid over secretion
leads to a condition
known as Grave’s
disease which is
characterized by
accelerated metabolic
processes.