Transcript Homeostasis

Homeostasis
regulation
Homeostasis is
• Maintaining a stable internal environment
• Staying within “normal” boundries
• No spikes too high or too low
Examples
• If your levels of calcium in the blood fell
too low, what does the body need to do?
• If your blood sugar is too high, what does
the body need to do?
• If you are not secreting enough growth
hormone, what does the body need to do?
Negative Feedback
• Is the most common method of control
used to maintain homeostasis
• Here’s how it works: a deviation occurs,
the body takes action to fix it. The
correction is the OPPOSITE or negative
direction from the problem
• For example, if your body temp is too high,
you will LOWER it; if a hormone level is
too low, you will turn on its production
Negative Feedback
• If the thyroid is not secreting enough
hormone, the body will stimulate the
release of the missing hormone. When
the level rises to normal, it will shut off the
production and secretion of the hormone.
• Self-regulating.
Negative Feedback Loop
Examples
• You will jigsaw to review 4 examples of
homeostasis
• You will become an expert on one
example, and then return to your original
table group to teach them about it.