We take water for granted. Though we drink it throughout the day, though we cannot function without it, and though it is present in all life forms on Earth, we rarely stop to think about what makes up water and how it operates. There is more to water than just H2O. In the following paragraphs, I will divulge the details of water in terms of its exact composition, its significance on Earth, and how it affects life forms.

Though most people would say that water comprises H2O, or that its molecule has one oxygen and two hydrogen atoms, there is more to that statement that meets the eye. Water is a polar inorganic compound (does not contain carbon) that is a tasteless and odorless liquid at room temperature. It is almost colorless as well, with a touch of blue. Water is the most studied chemical compound and the simplest hydrogen chalcogenide (Greenwood, Norman N.; Earnshaw, Alan). At normal terrestrial conditions, water takes the form of a liquid, solid, and gas. In fact, it is the only chemical substance on Earth that can exist as three states naturally. Water is so unique and precious to Earth that there are 40 anomalies that comprise water. For example, when water freezes, it expands about 9%, and that “warm water vibrates longer than cold water” (fathersergio.wordpress.com).

Water might be Earth’s greatest resource. About 71% of Earth is covered with water, and all life forms on Earth require water to survive. Thus, without water, there would be no life on Earth. Humans use water in more ways than any other species on the planet: cooking, washing their bodies, washing clothes, washing cooking eating utensils, keeping residencies and communities clean, recreation such as swimming pools, maintaining gardens, spiritual practices, farming, drinking, fire extinguishing, and more (Department of Health). All this requires a massive amount of water, and on Earth, the total water supply is approximately a volume of 1,338,000,000 km3. Most of the water on Earth is sea water, but it is also in the atmosphere as a solid, liquid, and gas (Gleick, P.H., ed.). Even below the ground, there are aquifers. Basically, water is everywhere we can imagine on Earth, and flows through each life form, no matter what it is. Also, through the water cycle, with evaporation, precipitation, and runoff, water is constantly flowing through Earth.

But what happens when life forms consume water? Water allows organic organisms to replicate, it acts as a solvent, and it is key in metabolic processes. Specifically, water is taken from molecules to grow bigger molecules; in contrast, water is also used to create smaller molecules by breaking bonds. In addition, water is essential to photosynthesis and respiration. According to the Royal Society of Chemistry, “Photosynthesis is the process by which plants, some bacteria and some protistans use the energy from sunlight to produce glucose from carbon dioxide and water. This glucose can be converted into pyruvate which releases adenosine triphosphate (ATP) by cellular respiration. Oxygen is also formed” (RSC). Furthermore, water is the basic component of acid-base neutrality and enzyme function. Shmoop describes water’s acid-base neutrality as such: “When water meets up with a base (like NH3), it acts as an acid by transferring a proton to the base. Alternatively, when water meets up with an acid (like HCl), it acts as a base by accepting a proton from the acid. What if, by some strange twist of fate, water meets itself? Suddenly, the curtain of water’s double-life deception is pulled and water-as-an-acid must face water-as-a-base” (Shmoop Editorial Team). In terms of enzyme function, “Enzymes require a certain level of water in their structures in order to maintain their natural conformation, allowing them to deliver their full functionality. In addition, depending on the type of the reaction, water can be a substrate (e.g., in hydrolysis) or a product (e.g., in esterolysis) of the enzymatic reaction, influencing the enzyme turnover in different ways. It is found that regardless of the type of reaction, the functionality of enzyme itself is maximum at an optimum level of water, beyond which the enzyme performance is declined due to the loss in enzyme stability” (Rezaei K., Jenab E, Temelli F.). As you can see, without water, our normal body functions would not exist and operate.

We use water throughout our days without much thought to its importance. It is the most essential chemical compound on Earth, as without it, no life would exist on this planet. Humans and animals alike use water daily for not only sustaining life, but for enjoyment as well. Each day, I believe we should give some thought or appreciation to the significance of water in our lives, and how it fuels our planet.


Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. p. 620. ISBN 0-08-037941-9.

“Forty-one Anomalies of Water.” fathersergio.wordpress.com. 2011 [last update].

“1 Water – its importance and source.” Department of Health | 1 Water – its importance and source, www.health.gov.au/internet/publications/publishing.nsf/Content/ohp-enhealth-manual-atsi-cnt-l~ohp-enhealth-manual-atsi-cnt-l-ch6~ohp-enhealth-manual-atsi-cnt-l-ch6.1.

Gleick, P.H., ed. (1993). Water in Crisis: A Guide to the World’s Freshwater Resources. Oxford University Press. p. 13, Table 2.1 “Water reserves on the earth”. Archived from the original on 8 April 2013.

“Photosynthesis.” RSC, www.rsc.org/Education/Teachers/Resources/cfb/Photosynthesis.htm.

Shmoop Editorial Team. “Chemistry Water as an Acid and Base – Shmoop Chemistry.” Shmoop, Shmoop University, 11 Nov. 2008, www.shmoop.com/acids-bases/water-acid-base.html.

Rezaei K., Jenab E, Temelli F. Effects of water on enzyme performance with an emphasis on the reactions in supercritical fluids. Pubmed.gov.


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