Chapter 9, Problem S2.3BYB

Summary Introduction

To analyze:

The properties and role of water in the movement of nutrient in plants.

Introduction:

Water plays an important role in plant life. For proper growth and development, and for maintaining all the physiological activities of the cell, a proper balance of water is very much necessary. Water is released from the plant and again produced in the plant to keep it in a balanced state.

Explanation of Solution

In a plant’s life, the requirement of water is always maintained so that the plants are able to survive in any environmental conditions. There are some properties of water which helps the movement of nutrients in plants and other functions too. Some of the properties of water are:

The Polarity of water: Water is made up of two molecules of hydrogen and one molecule of oxygen where the two-hydrogen atom binds to one side of the oxygen creating an imbalance in the polarity. The hydrogen atom will have the least positive charge and more negative charge is developed in the oxygen atom. This always keeps the water in the liquid state. It is very easy for plants to absorb water in its liquid state from the soil and transport it to other parts. Because of its difference in polarity, the shape of water can easily be changed to droplets.

Cohesion and Adhesion: The more electronegative property of the oxygen side in the water attracts the positive hydrogen side of other water molecules forming a hydrogen bond between them. This results in clumping of water molecules together forming droplets and once they stick to the xylem, it helps in their easy movement to a larger distance.

Capillary Property: The capillary action of water brings the water molecules on the surface of the leaf through the xylem. The evaporation at the surface of the leaf and the cohesion-adhesion properties of water makes the water molecules to move in a narrow capillary tube and maintain the continuity of water columns in plants.

High specific heat: The water droplet, once they reach the surface of the leaf, will evaporate and release oxygen and hydrogen molecule in the atmosphere. The oxygen and hydrogen molecules are released in an exchange process. The atmosphere will release carbon dioxide required by the plants only when the plants release oxygen and hydrogen.

Conclusion

Plants absorb water through capillary action from the soil through their roots via the xylem. When the water reaches the surface of the leaf, it is evaporated and is lost in the form of oxygen and hydrogen. The properties of water make them simple and easy for the plants to absorb it.