The Endocrine
System
Homeostasis and Feeback
Learning Outcomes
★ I can describe how hormones help to
maintain homeostasis through feedback
systems.
Homeostasis
Homeostasis is a process that occurs when a
constant internal environment is maintained
despite changes in that environment
Homeostasis
Changes are constantly occurring in your
body but you are able to respond to these
changes effectively instead of dropping dead
because of them (most of the time).
Homeostasis
Homeostasis is regulated through the use of
the endocrine system.
Endocrine glands help to secrete hormones
to maintain homeostasis.
Homeostasis
All homeostatic control systems have three
functional components:
1. Receptor
2. Coordinating Centre
3. Effector
Homeostasis
Receptors send information to the
coordinating centres which relay information
to the effector which helps to restore a
normal balance
Homeostasis
Example:
When carbon dioxide levels increase during
exercise, chemical receptors in the brain are
stimulated. Nerve cells carry impulses to
muscles which increase the depth and rate of
breathing. This brings the body back to a
state of equilibrium/homeostasis.
Feedback Systems
There are two forms of feedback systems in
your body:
1. Negative Feedback
2. Positive Feedback
Negative Feedback
Negative Feedback
Like with a thermostat, negative feedback
systems are activated to restore conditions to
their original state.
These are the most common feedback
systems in your body.
Negative Feedback
Negative feedback systems prevent small
changes from becoming too large.
Positive Feedback
The less common feedback system, this
system is a process where a small change is
amplified or increased.
One example that uses this system is a
woman giving birth.