Question

Through which plant structure does water move by capillary action?

Answer 1

Xylem

Explanation:

Plants have two main structures that are capable of transporting water and sugar throughout the plant system namely, xylem and phloem, respectively. Water moves into the plant by means of several simultaneous actions aside from capillary action. But first, let us know the importance of water in plants.

Water is an essential material in plants since plant cells are composed of mainly water and dissolved nutrients commonly found in the central vacuole (occupies 90-95% of the entire plant cell). Without water, plants are not able to proceed or function photosynthesis and cell respiration—processes which are the main important activities in plant system to produce energy and food for itself and to its consumers.

In reality plants are watered from soil. The root hairs will absorb the water and the nutrients present in soil by means of osmosis (net movement of molecules from high solute concentration, which in this case are the nutrients present in soil, to lower solute concentration.

Water molecules move upward by capillary action that is supported by two actions, cohesion and adhesion). Water molecules are known to be highly cohesive (attraction between same type of molecules) while adhesion is the attraction between the water molecule and the surface of the xylem vessel (you know that it's a xylem vessel if the diameter of the cell is wider than other cells and it is highly lignified).

Aside from the capillary action, water moves by the force exerted in transpiration, where water proceeds to where it is needed—that is, the leaves (sink) as they contain the photosynthetic organelle, chloroplast. Upon receiving water molecules, photosynthesis (dark reaction) will now occur.

The presence of dew on the surface of leaf is caused by excessive water supply inside the plant system. Water leaves out of the system through stomata (stomata are more numerous in the abaxial part (bottom) than the adaxial (top)). In return, by releasing water, the plant cools down. Presence of dew also an indication for humidity in the environment.