The hydrosphere is composed of all of the water on or near the earth. This includes the oceans, rivers, lakes, and even the moisture in the air. Ninety-seven percent of the earth's water is in the oceans. The remaining three percent is fresh water; three-quarters of the fresh water is solid and exists in ice sheets.
It is so easy sometimes to take our hydrosphere for granted, and we seldom take the time to really think about the role that this part of the planet plays in keeping us alive. Below are just some of the very important functions of water in the hydrosphere. The hydrosphere provides an important place for many animals and plants to live.
This is important in helping to regulate temperatures on earth so that they stay within a range that is acceptable for life to exist. Humans use water in a number of ways. Drinking water is obviously very important, but water is also used domestically and in industry. Water can also be used to generate electricity through hydro-power. Each cell in a living organism is made up of almost 75\% water, and this allows the cell to function normally. In fact, most of the chemical reactions that occur in life, involve substances that are dissolved in water. Without water, cells would not be able to carry out their normal functions, and life could not exist. The presence of these substances is critical for life to exist in water.
It is important because we need the water to live. All living things like animals, plants need water to survive. All the things that come out from the water can be really useful to us. Fish, seaweed and such, can be used for food.These are just a few of the very important functions that water plays on our planet. Many of the functions of water relate to its chemistry and to the way in which it is able to dissolve substances in it.
