Unit 1: Wellness and Homeostasis

Learn how and where osmosis takes place in the digestive system and excretory system and the role of osmosis in kidney dialysis.

What are your teeth made up of? What chemistry is at work in your mouth? Why do some people get cavities even if they brush regularly?

Temperature is an important part of life on Earth and life in space. This backgrounder explains what temperature is, how it affects people and how it is controlled on the International Space Station.

Spending time outside has important physical and psychological benefits. It can even help you learn better!

What's tasty, abundant and high in protein and vitamins? Bugs! Bugs feed about 2 billion people each day. They also hold promise for food security and sustainability.

What is the difference between sound and noise? How do they affect your hearing? And is noise always a bad thing?

This backgrounder explains what noise is, how it is measured, and how it affects our hearing, wellness and more.

This backgrounder explains what light is, how it is measured, and how it affects people on Earth and astronauts on board the International Space Station.

Humidity is an important part of life on Earth and life in space. This backgrounder explains what humidity is, how it is measured and how it affects us both mentally and physically.

How do our bodies get cold? How do sleeping bags keep us warm?

Panic attacks are scary and they upset your body’s chemical equilibrium. Learn what happens to acids & bases in your circulatory system during a panic attack.