Transcript Equilibrium and Negative Feedback

Equilibrium and
Negative Feedback
Equilibrium

If something is in equilibrium it is
balanced
Homeostasis
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The body’s way of staying stable on the
inside despite what happens outside
Sweating to cool off
 Shivering to warm-up
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Negative Feedback

Process that turns itself off when condition
is met

Thermostat
-too hot AC turns on
-Cools off AC turns off
-Warms up AC turns on….
Negative Feedback Ex. #1

Maintaining Temperature
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
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Body must stay at constant temperature
Too hot Body Sweats
Too cold Body Shivers
Negative Feedback Ex. #2
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Maintain Glucose levels
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Glucose-sugar


too much or too little sugar can kill you
Hormone: chemical that tells body what to
do

Insulin: hormone that tells cells to take in sugar
1.
2.
3.
4.
5.
Eat sugar
Pancreas produces insulin
Tells cells to take in sugar
Cells take in sugar
Pancreas stops producing insulin
Diabetes

Pancreas does not produce enough insulin
Pancreas produces too much insulin
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Must manually regulate sugar and insulin
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Negative Feedback Ex. #3
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Water Equilibrium in plants
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Diffusion: Movement of water through a
membrane
Moves from full to empty
 Moves from fresh to salty
 High to low
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Water Equilibrium in Plants

Turgor Pressure: the pressure of water on
a cell wall in a plant
Turgor pressure high: no water comes in
 Turgor pressure low: water moves into plant
*More Turgor pressure the happier a plant looks
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Turgor Pressure
Negative Feedback #4
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Water equilibrium in animals
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Thirsty-drink water
Kidney’s function regulate water remove
waste
Too much water: urine is more clear (little urea),
urinate more frequently
 Not enough water: urine is dark (more urea),
smells bad, urinate less
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