How do plants breathe? Practical study of the issue

It is established that the biochemical reactions taking place in the human body and animals are the same. Do plants breathe? In many experiments, the scientists gave a positive answer to this question. Oxygen is necessary for the oxidation of organic substances. This releases the energy that is contained in the molecules. But if a person has a mouth, lungs, a nose through which oxygen enters the body, how do plants breathe? About this later in the article.

General information

The atmosphere of the Earth in ancient times was deprived of oxygen. However, there was quite a lot of carbon dioxide . In the process of evolution, plants developed the ability to absorb it. As a result, the energy of sunlight was converted into nutrients, and oxygen was released into the atmosphere, which gave life to other organisms. One of the first experiments, during which it was clarified how the plants breathed, was the experiment with beets and cabbage. First, cultures were grown outdoors. Then half of them were placed in a chamber where the oxygen content was about 2.5%. The other part remained in the air, in which O ₂ was 21%. Lighting both those and others was carried out round the clock. It was assumed that plants placed in the chamber would die without oxygen. However, six days later their weight was significantly higher than those who remained in the air. How do plants breathe without oxygen? About this further.

How do plants breathe in the light and in the dark?

The fact is that representatives of the flora are able to use solar energy very efficiently. When darkness comes, there is a kind of "switching" from one source to another. How do plants breathe in the light and in the dark? When solar energy enters, organic substances are synthesized. At the onset of darkness, the process of oxidation of the compounds takes place. In the latter case, they speak of "dark" breathing, and in the first case they speak of "light" breathing. Ability to switch this allows you to save internal energy reserves. But representatives of the flora breathe in the light, however, this process does not bring them benefits. Absorbing oxygen, plants produce carbon dioxide. He is their main food. In this regard, growth is somewhat slowing. There are, however, also such representatives of the flora, to whom the light does not interfere to develop. Light breath, for example, is not found in sugar cane and corn.

Causes of light breathing

The beginning, as scientists suggest, has become a symbiosis of photosynthetic primitive organisms with nonphotosynthesizing. By symbiosis we mean mutual participation in processes, which is useful to both sides. Living in the water, small photosynthetic absorbed from the environment carbon dioxide, thereby releasing oxygen. If there were no breathing, absorbing O ₂ organisms in the medium, unbearable conditions would be created for photosynthetic ones. But in the process of evolution, those representatives of the organic world also survived, which were also useful for non-photosynthetic ones.

One of the compounds that is formed during photosynthesis is glycolic acid. This substance is also released by some modern algae. As a result, non-photosynthesis was obtained from photosynthetic glycolic acid. This, in turn, contributed to increased oxygen consumption for the oxidation of the compound.

Conclusion

Glycolic acid is the same substance that, during several biochemical reactions, oxidizes and forms carbon dioxide. Accordingly, it can be concluded that the more oxygen in the air, the more glycolic acid is formed. This provides a greater intensity of light breathing. As a result, more carbon dioxide is released on Wednesday. Scientists suggest that a similar principle was developed in plants and the ability to regulate light breathing in accordance with the level of carbon dioxide in the air. Organisms not only absorbed from the environment oxygen, harmful to photosynthesis, but also isolated carbon dioxide, which they needed.

Experiments

You can see in practice how the plants breathe. 6th grade of the school biology program highlights this issue in great detail. To observe the process, you can take a leaf of a room flower. In addition, you will need a magnifying glass, a transparent container filled with water, a cocktail tube. Experience proving that plants breathe allows not only to understand the course of the process, but also to reveal the need for a sample in oxygen. On the cut sheet, you can see small holes. Part of the sample is immersed in water, with a distinction of bubbles. There is another way to see how the plants breathe. To do this, take a bottle, pour water into it, leaving unfilled for about two to three centimeters. The sheet on the long stem is inserted so that its tip is immersed in the liquid. The opening of the bottle is densely covered with plasticine (instead of cork). It makes a hole for the straw, which is inserted so that it does not touch the water. Through the straw you should suck the air out of the bottle. From the stem immersed in the water, bubbles begin to separate.