Water- Why is it needed by the plants?

             Long ago when there was nothing...nothing means absolutely nothing, the basic elements- Carbon, oxygen, hydrogen and nitrogen were ruling the earth. Because of series of changes that took place, the two molecules of Hydrogen decided to get attached with one molecule of Oxygen. Water was formed. Now, the arrival of first organism was awaited. The first organism got its existence inside water only. Why? Because it was developed basically, in such a way that it was completely- 1. Corresponding to water 2. made according to the chemical nature of water  3. made inside water. And if it is so water-oriented, then it is obvious that it should require water for its growth, development and maintenance. Even if billions of years gone, the thing are not changed yet.
             Although this first organism got bifurcated later on into plants and animals, the necessity of water remained the same. (You can observe how many times the word- “water” is used in the first paragraph!) If water is so important for life of the plants, they must develop a system that absorbs and conducts the water towards every part of the plant. That is why it uses the principles like osmosis, diffusion, imbibition etc.
             The plant also shows formation of root hair, different pathways for absorption and conduction of water. The water gets lost in the atmosphere quickly, but the plant requires it to be stored. Hence it develops the structures like stomata, guard cells etc. The water, once in, it raises throughout the length of the plant by cohesion and adhesion of water molecules.
             As water is absorbed, it is lost via transpiration through aerial parts of the body. This creates a transpiration pull. To overcome such water loss, the plants show stomata that open and close, thus regulating the water loss through them.
             The transpiration has both harmful as well as useful effects. It maintains the water level inside plant body as well as it may lead to desiccation of the plant parts. Hence it is called as necessary evil.   

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