Introduction

Plants are known for their ability to transport water from roots to leaves. This process involves several steps including absorption, movement, and release of water. Cohesion is a critical factor that helps in the efficient transportation of water in plants. In this article, we will discuss how cohesion helps plants transport water.

What is Cohesion?

Cohesion is the attractive force between water molecules which holds them together. This force is primarily due to the hydrogen bonds between the oxygen and hydrogen atoms in water molecules. Because of cohesion, water is able to form a continuous column in the xylem vessels of plants.

Water Transport in Plants

Water transport in plants occurs through two main structures – the xylem and phloem. The xylem is responsible for transporting water and minerals from roots to leaves. The phloem, on the other hand, transports food and nutrients from leaves to other parts of the plant. In the xylem, water moves from areas of high concentration to areas of low concentration, driven by osmotic pressure.

Cohesion in Xylem Transport

Cohesion plays a crucial role in the xylem transport of water. As water is transported through the xylem, it forms a continuous column due to the cohesive forces between water molecules. This column of water is pulled up due to transpiration – the loss of water from leaves in the form of vapor. Transpiration creates a negative pressure in the leaves which draws water up through the roots and xylem.

Adhesion and Capillary Action

Adhesion is another important factor that helps in the transport of water in plants. Adhesion is the attractive force between water molecules and the xylem walls. As water moves up the xylem, it adheres to the walls of the xylem and is pulled up due to the cohesive forces between water molecules. Capillary action also plays a role in the transport of water in plants. Capillary action is the ability of water to move in narrow tubes against gravity. This is due to the combination of cohesive forces between water molecules and adhesive forces between water and the walls of the tubes.

Cohesion and Water Conservation

Cohesion not only helps in the transport of water in plants but also plays a crucial role in water conservation in plants. Cohesion allows plants to minimize their water loss by closing their stomata during periods of water stress. When stomata are closed, transpiration reduces, and the column of water in the xylem remains intact due to cohesive forces.

Conclusion

Cohesion is an important factor that helps plants in the efficient transport of water from roots to leaves. Cohesion allows water to form a continuous column in the xylem vessels due to the cohesive forces between water molecules. This column of water is pulled up due to transpiration and is aided by adhesion and capillary action. Cohesion also plays a crucial role in water conservation in plants by helping to minimize water loss through stomata closure during periods of water stress.