3. Most body systems maintain
homeostasis by using feedback
mechanisms. When the brain
receives messages from the body
about an internal change in one
of its systems, it works to restore
the system to its normal state.
The levels of hormones in the
body are controlled by feedback.
It is important that the amount of
hormones in the body is kept at
4. FEEDBACK MECHANISM
a physiological regulation
system in a living body that
works to return the body to
its normal internal state
the process through which
the level of one substance
influences the level of
another substance
5. Feedback mechanisms
in menstrual cycle:
1. Follicle stimulating
hormone (FSH)
stimulates the ovaries to
release estrogen. High
levels of estrogen then
prevent the further
production of FSH.
6. Feedback mechanisms in
menstrual cycle:
2. Estrogen also stimulates
the release of luteinizing
hormone (LH) from the
pituitary gland, which in turn
controls the production of
progesterone. High levels of
progesterone then inhibit
the further release of LH.
9. Homeostasis is the state
reached when each part of
the body is functioning in
equilibrium with other parts.
This is attained through
the regulation of the bodily
functions by the endocrine
and nervous systems.
10. Both the nervous system and the
endocrine system are important in
enabling the body to maintain
homeostasis.
Homeostasis depends on the ability
of different systems in your body to
communicate with one another.
To maintain homeostasis,
messages must be generated,
delivered, interpreted, and acted
upon by your body.
The nervous system and the
endocrine system are the
communication networks that allow
you to respond to changes in your
environment countless times each
11. TO ACHIEVE HOMEOSTASIS, THE
NERVOUS SYSTEM AND THE
ENDOCRINE SYSTEM MAINTAIN A
NORMAL RANGE OF THE
FOLLOWING VARIABLES:
a. Body temperature,
b. Amount of water in the
body,
c. Amount of metabolic waste
in the cell,
d. Blood calcium levels,
e. Hormones in the blood
12. WHAT IS A NEGATIVE
FEEDBACK
MECHANISM? WHAT
IS A POSITIVE
FEEDBACK
MECHANISM?
13. NEGATIVE FEEDBACK
MECHANISM
the body responds in
such a way as to reverse
the direction of change.
a stimulus causes the
release of a substance
whose effects then
inhibit further release