Homeostasis - Unit 3 Lesson 5

Simply put, homeostasis is a fancy word for living things doing things to ensure that they remain living. Too hot? Your body begins to sweat so that your cells do not overheat. Too cold? Your body begins to shiver, which creates heat, which keeps your cells working. These are two common examples of homeostasis. But there are many, many more examples.

Before that, though, let’s break down the word homeostasis. The prefix “homeo” means “same” and the word-part “stasis” means “remain” (like “stationary” or “stationed”). So homeostasis means “remain the same”. And that’s what different homeostatic processes attempt to do - keep the environment inside the organism balanced.

Take for example this little paramecium (para-ME-see-um). It needs to pump out excess water from itself (remember, a paramecium is a single-celled organism).

Okay, I know - not very exciting. But it’s exciting for the paramecium because if it didn’t have an ability to pump water out of itself the paramecium would literally explode from excess water. This is an example of homeostasis because the paramecium is maintaining its internal environment by getting rid of excess water.

You can explore more with the paramecium with this Gizmo.

Okay, on to the more interesting examples. Once again, the Amoeba Sisters give us some excellent illustrations. After you watch the video add your responses to these questions in your notes.

Summarize one of the examples of homeostatic processes. Explain the negative feedback loop of this process.

Does a thermostat maintain homeostasis for a home? Explain the negative feedback loop of a thermostat.