Fresh Water: Necessary for Life

Water. It’s everywhere! Animals have to drink it to stay hydrated, plants need it to grow, and fish need it to breathe and swim. Water is even in the air we breathe. 

Water is the most important nutrient for all living organisms on Earth. Without water, there wouldn't be life on Earth. In fact, one of the first things scientists look for when searching for life on other planets is evidence of water.

For humans, water makes up about 65% of our bodies. We have water in our blood, in every cell, and in all our tissues and organs. Water plays a major role in keeping our bodies healthy and strong, even more than food does! A person can live approximately 3 weeks without food as long as they have water, but a person will die after just one week without water. It’s that important!

The saltwater oceans hold 97 percent of the water on Earth. Glaciers hold 2 percent of the remaining water in the form of ice. Only 1 percent of the water on Earth is the liquid fresh water that all plants and animals depend on in order to survive.

The hydrosphere includes all water found on Earth, and the hydrosphere interacts with the geosphere, atmosphere, and biosphere to support life on Earth. Let's dive deeper into the different phases of water. We'll see how water is recycled on Earth through the water cycle and review the many different bodies of water that occur here on our beautiful blue planet.

Answer the following questions based on what you already know.