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.