The endocrine system:
The endocrine system depends on chemical messengers called hormones produced by
glands that have no ducts. The hormone is composed of a protein and is released into the
blood, which transports it throughout the body. The term ‘hormone’ comes from the
Greek word meaning ‘excite’. Hormones do excite their target organs, usually by
stimulating a change in some metabolic activity. Hormones never work in isolation;
rather they work together to form an integrated system of control.
The hypophysis (pituitary gland):
The pituitary gland is the size of a pea, weighing only half a gram, the hypophysis to the
brain by a stalk. It produces 9 hormones.
Gland: Where is Hormone: Function: Disorder: Symptoms: Cause:
it found:
Pituitary Borne Growth Stimulates the growth Giantism Excessively tall Over secretion of
on a hormone of bones and muscle growth hormone
stalk tissue. Dwarfism An in proportion Under secretion of
from the midget growth hormone
brain Acromegaly Big hands, feet and Over secretion of
face growth hormone
after puberty
ADH Stimulates the
reabsorption of water
by the nephron
(kidney).
TSH Stimulates thyroid to
produce more thyroxin.
FSH Stimulates the growth
of follicles in the ovary.
LH Causes ovulation.
Causes the empty
Graafian follicle to turn
into a corpus luteum.
ICSH Stimulates production
of testosterone by
interstitial cells
The thyroid gland:
Gland: Where is Hormone: Function: Disorder: Symptoms: Cause:
it found:
Thyroid In the Thyroxin Controls the Cretinism Mentally and physical Lack of thyroxin in
gland neck, in (contains metabolic subnormal an infant
front of iodine) rate. It causes Hypothyroidism Weight gain, hair Lack of thyroxin in
the (Iodine is the body to (myxedema) falling out, lethargic an adult
trachea necessary burn its and coarsening
and just for a normal available features
below the functioning carbohydrate Hyperthyroidism Weight loss, poppy Over secretion of
larynx thyroid) s rapidly and eyes and hot and thyroxin in an adult
release sweaty
energy. Goitre Swelling in the neck Shortage of iodine
The endocrine system depends on chemical messengers called hormones produced by
glands that have no ducts. The hormone is composed of a protein and is released into the
blood, which transports it throughout the body. The term ‘hormone’ comes from the
Greek word meaning ‘excite’. Hormones do excite their target organs, usually by
stimulating a change in some metabolic activity. Hormones never work in isolation;
rather they work together to form an integrated system of control.
The hypophysis (pituitary gland):
The pituitary gland is the size of a pea, weighing only half a gram, the hypophysis to the
brain by a stalk. It produces 9 hormones.
Gland: Where is Hormone: Function: Disorder: Symptoms: Cause:
it found:
Pituitary Borne Growth Stimulates the growth Giantism Excessively tall Over secretion of
on a hormone of bones and muscle growth hormone
stalk tissue. Dwarfism An in proportion Under secretion of
from the midget growth hormone
brain Acromegaly Big hands, feet and Over secretion of
face growth hormone
after puberty
ADH Stimulates the
reabsorption of water
by the nephron
(kidney).
TSH Stimulates thyroid to
produce more thyroxin.
FSH Stimulates the growth
of follicles in the ovary.
LH Causes ovulation.
Causes the empty
Graafian follicle to turn
into a corpus luteum.
ICSH Stimulates production
of testosterone by
interstitial cells
The thyroid gland:
Gland: Where is Hormone: Function: Disorder: Symptoms: Cause:
it found:
Thyroid In the Thyroxin Controls the Cretinism Mentally and physical Lack of thyroxin in
gland neck, in (contains metabolic subnormal an infant
front of iodine) rate. It causes Hypothyroidism Weight gain, hair Lack of thyroxin in
the (Iodine is the body to (myxedema) falling out, lethargic an adult
trachea necessary burn its and coarsening
and just for a normal available features
below the functioning carbohydrate Hyperthyroidism Weight loss, poppy Over secretion of
larynx thyroid) s rapidly and eyes and hot and thyroxin in an adult
release sweaty
energy. Goitre Swelling in the neck Shortage of iodine
