Transcript pituitary gland

Regulation and Control
the water content of the body
water leaves the body via the lungs when we
breathe out and via the skin when we sweat, and
excess water is lost via the kidneys in the urine
temperature
to maintain the temperature at which enzymes
work best
blood sugar levels
to provide the cells with a constant supply of
energy.
The conditions inside the body must be controlled
within narrow limits. This is called homeostasis.
These include water content, ion content, body
temperature and blood glucose concentration.
The pancreas monitors and
controls blood glucose
concentration. It produces
a hormone called insulin
that reduces blood glucose
levels.
Diabetes is a disease where the concentration of glucose in the
blood is not controlled properly by the body.
In type 1 diabetes, the pancreas does not produce enough insulin.
There are 2 types of treatment:
•Careful monitoring of food intake,
with particular care over
carbohydrates.
•Injecting insulin into the blood
before meals. The extra insulin causes
glucose to be taken up by the liver
and other tissues so the blood glucose
concentration stays normal.
Temperature regulation
Human enzymes work best at 37ºC, so the body’s temperature
needs to be controlled.
A part of the brain called the thermoregulatory centre monitors
and controls body temperature.
It gathers information as from temperature receptors (nerve
endings) in the brain and the skin.
The thermoregulatory
centre is the part of
the brain that monitors
and controls body
temperature.
Homeostasis
The conditions inside the body must be controlled within
narrow limits.
This process is known as ______________.
The conditions which must be controlled include water
content, ion content, body temperature and __________
glucose concentration.
The_________ ________ is the part of the brain that
monitors and controls body temperature.
The _______________ monitors and controls blood
glucose concentration. It produces a hormone called insulin
that reduces blood ___________ levels.
Diabetes is a disease which can be caused by insufficient
_________.
The endocrine system
The endocrine system co-ordinates the
body’s organs so that they work together.
The endocrine system is based on the
production of chemical messengers called
hormones.
Hormones are produced by glands
(endocrine glands) in different parts of
the body. These chemical messengers
produced in very small quantities and
transported in the blood.
Hormones control body processes that require several
organs of the body to interact.
Many processes in the body are controlled by chemical
substances called hormones.
Hormones are secreted by glands and are transported
to their target organs in the bloodstream.
adrenalin
vital organs,
eg liver and
heart
Prepares body for action: “fight or flight”.
ovary
oestrogen
ovaries,
uterus,
pituitary
gland
Controls puberty and the menstrual cycle in females;
stimulates production of LH and suppresses the
production of FSH in the pituitary gland.
ovary
progesterone
uterus
Maintains the lining of the womb; suppresses FSH
production in the pituitary gland.
pancreas
insulin
liver
Controls blood sugar levels.
pituitary
gland
anti-diuretic
hormone
(ADH)
kidney
Controls blood water level by triggering uptake of
water in kidneys.
pituitary
gland
follicle
stimulating
hormone
(FSH)
ovaries
Triggers egg ripening and oestrogen production in
ovaries.
pituitary
gland
luteinising
hormone (LH)
ovaries
Triggers egg release and progesterone production in
ovaries.
adrenal
gland
testes
testosterone
male
reproductive
organs
Controls puberty in males.
Endocrine glands – thyroid
thyroid
Produces the hormone
thyroxine:
 Regulates rate of metabolism.
 Excess causes hyperactivity.
 Deficiency causes overweight
and sluggishness.
Endocrine glands – adrenal
glands
Produce the hormone adrenaline.
Adrenaline causes the ‘fight or
flight’ response resulting in:
adrenal
glands
Increased heart rate and breathing
rate.
Blood diverted to the muscles.
Increased respiration to increase
the amount of glucose in the
blood.
Endocrine glands – reproductive
organs
In females, ovaries produce several
hormones:
ovaries
oestrogen
 Controls the development of
female secondary sexual
characteristics.
 Regulates menstrual cycle,
progesterone
 Thickens uterine wall.
 Prevents contractions until a baby
is being born.
Several other hormones are involved in the menstrual
cycle of a woman;
FSH is secreted by the
pituitary gland and causes eggs
to mature in the ovaries, it also
stimulates the ovaries to
produce hormones including
oestrogen.
Oestrogen inhibits the
production of more FHS and
stimulates the pituitary gland to
produce a hormone called LH.
LH causes the mature egg to be
released from the ovary
Endocrine glands – pituitary
pituitary
gland
gland
In women,
follicle stimulating hormone (FSH)
and
leutenising hormone (LH)
Are both produced by the pituitary
gland.
The levels of
each
hormone
fluctuate
throughout
the
menstrual
cycle.
Oh Ovary!
How lovely and round are you!
Along with your twin,
Half cells do you make.
To travel down the fallopian
On the journey to its final resting
place.
Perhaps along the way,
A sperm you will meet.
To mate and to multiply,
Till 9 months past,
A screaming beast do you create!
The uses of hormones in controlling fertility
include:
Oral contraceptives (“the pill”) contains
oestrogen or a mixture of oestrogen and
progesterone. The oestrogen stops FSH
therefore preventing eggs from maturing in the
ovaries.
FSH can be given as a ‘fertility drug’ to a
woman whose own level of FSH is too low to
stimulate eggs to mature.
Endocrine glands – reproductive
organs
In males, testes produce the
hormone testosterone:
testes
Promotes the development of male
secondary sexual characteristics
such as a hairy chest and deep
voice.
Endocrine glands – pituitary gland
pituitary
gland
The pituitary gland produces
several other hormones:
growth hormone
Promotes bone and muscular
growth.
antidiuretic hormone (ADH)
Controls reabsorption of water into
the blood by kidneys.
thyroid stimulating hormone
(TSH)
Controls the endocrine function of
the thyroid gland.
Endocrine glands – pancreas
Produces the hormone insulin:
pancreas
Controls the conversion of blood
glucose to insoluble glycogen,
which is stored in the liver.
Increases metabolic rate by
stimulating cellular glucose uptake.
Increases protein synthesis in some
cells.
Match up the hormone to the gland
Adrenal
Thyroid
Testosterone
Ovaries
Thyroxine
Insulin
Adrenaline
Pancreas
Oestrogen and
Progesterone
Testes
The Menstrual Cycle
1) What are the roles of the hormones LH, FSH
and Oestrogen?
2) What effect would taking oestrogen tablets
have?
3) Which hormone could be used to promote
fertility?