Evaporation of water by plant organisms

Evaporation of water, or transpiration, is a very important part of the life of a plant. Water is absorbed by the root system together with the mineral substances dissolved in it, which are simply necessary for normal growth of the organism. Most of the absorbed water is evaporated by the leaves.

The role of water in the development of the plant organism . Water - a very important element and its role in the life of the plant is difficult to overestimate. Due to water, it supports the turgor of cells, due to which the leaves and stems become elastic and elastic. Without enough fluid, the plant quickly wilt.

In addition, along with water absorbed by the roots of mineral substances are distributed to all organs of the plant. Moisture also protects the body from overheating. Evaporation of water by plants occurs mainly through stomata - specialized formations on leaves. In some measure, transpiration is also carried out by the whole body of the plant through the coverslips.

Stomata and their structure . The evaporation of water by leaves occurs mainly through specialized structures called the stomata. The stomata consists of two closing cells of crescent shape, between which there is a small gap. The inner wall of the closing cells is thicker, and the outer wall is thin. Under the structure is a small cavity.

Stomach can be on either side of the leaf. But in the set of plants they are located on its inner part. But in aquatic plants, whose leaves are in contact with water (for example, water lilies), - on the outside of the leaf.

It should be noted that the stomata are responsible not only for the evaporation of water, but also for gas exchange with the atmosphere - oxygen and carbon dioxide pass through them .

Evaporation of water: how does it happen? As already mentioned, transpiration can also occur through the covers of the entire body of the plant organism - in this case it is called the cuticular. Leaves, stem and other organs of the young plant are covered with a single-layered epidermis - moisture is removed through it. In more mature plants, a cuticle and wax ball is deposited on the outer surface, which protects the body from excessive loss of moisture and drying out. Therefore, cuticular transpiration in mature leaves is minimized.

The main evaporation passes through the stomata. To begin with, water moves through the vessels of the xylem, then passes through the cell walls to the intercellular spaces, from where it gathers into the podostic cavities.

The opening and closing of stomata is primarily affected by the amount of water. When moisture accumulates in the closing cells, they expand and take the form of a crescent - in this case the gap opens. If the water in the cells is not enough, they lose the turgor, their walls drop and close the crack.

The state of stomata is affected by the content of carbon dioxide. If its level in the tissues of the plant drops sharply, then the processes of opening the stomata are activated. And if the concentration of this gas is too high, the gap closes. That is why the stomata close at night, when the processes of photosynthesis stop.

Evaporation of water and its quantitative characteristics . Like any other process, transpiration has its quantitative indicators, which are used in agriculture, science and other spheres of human life.

For example, the intensity of transpiration shows how many grams of water are released by a part of a plant with a certain area per unit of time. Measuring the productivity of transpiration, we can say how much dry matter was accumulated by the plant during the evaporation of one kilogram of water. And having determined all these indicators, you can find out some individual characteristics of the plant species, establish what conditions are necessary for its productive growth.