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Homeostasis
Maintaining
a
stable
environment
Homeostasis
•  Process
by
which
organisms
keep
internal
conditions
relatively
constant
despite
changes
in
external
environments.
•  Endocrine
and
Nervous
Systems
play
the
biggest
parts
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Non‐Living
Example
•  Temp
drops
below
a
set
point
•  Thermostat
clicks
on
furnace
•  Furnace
heats
house
•  Temp
rises
above
a
set
temp
•  Thermostat
clicks
off
furnace
So
the
temperature
is
kept
within
a
narrow
range.
Parts
of
Homeostasis
•  Variable
–
what
is
being
balanced
•  Sensor
–
the
part
that
tells
if
there
is
a
good
balance
•  Integrator
–
sends
message
to
fix
problem
•  Effector
–
Gets
message
&
fixes
problem
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Feedback
Inhibition
(negative
feedback)
What
is
the
variable?
What
is
the
sensor?
What
is
the
integrator?
What
is
the
effector?
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Negative
Feedback:
Regulation
of
the
Endocrine
System
What
is
the
variable?
What
is
the
sensor?
What
is
the
integrator?
What
is
the
effector?
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