How do plants breathe? Practical study of the issue

It is established that the biochemical reactions occurring in humans and animals, are the same. Do plants breathe? In the course of many experiments on this question, scientists gave a positive answer.

Oxygen is required for the oxidation of organicsubstances. When this occurs, the release of energy, which is enclosed in molecules. But if a person has a mouth, lungs, nose through which oxygen enters the body, how do plants breathe? About this later in the article.

General information

Earth's atmosphere in ancient times was devoidoxygen. However, there was quite a lot of carbon dioxide. In the process of evolution, plants developed an 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 found out how plants breathe, was an experiment with beetroot and cabbage. First, crops 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 O₂ It was

21%.Lighting and those and others carried out around the clock. Plants placed in the chamber were supposed to die without oxygen. However, after six days, their weight was significantly higher than that of those who remained on 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 flora representatives are ablevery efficient use of solar energy. At nightfall, a kind of “switching” from one source to another occurs. How do plants breathe in the light and in the dark? When solar energy is supplied, organic matter is synthesized. When darkness occurs, the process of oxidation of compounds. In the latter case, they talk about "dark" breathing, and in the first - about "light". The ability for such a switch saves internal energy reserves. But representatives of the flora breathe in the light, but this process does not benefit them. Absorbing oxygen, plants emit carbon dioxide. He is their main food. In this regard, the growth slows down somewhat. There are, however, such representatives of the flora that the light does not prevent from developing. For example, sugar cane and corn do not have light respiration.

Causes of light respiration

Началом, как предполагают ученые, стал симбиоз photosynthesizing primitive organisms with non-photosynthetic. By symbiosis is meant mutual participation in processes, which is beneficial for both parties. Small photosynthetics living in the water absorbed carbon dioxide from the environment, releasing oxygen. Had a breathing, absorbing Oh₂ there were no organisms in the environment, then for photosyntheticsunbearable conditions would have been created. But in the process of evolution those representatives of the organic world, who were also useful for non-photosynthetics, survived.

Одним из соединений, которое образуется при Photosynthesis, is glycolic acid. This substance is released and some modern algae. As a result, non-photosynthetics obtained glycolic acid from photosynthetics. This, in turn, contributed to increased oxygen consumption for oxidation of the compound.

Conclusion

Glycolic acid is the very substance that, during several biochemical reactions, oxidizes and forms carbon dioxide.

Accordingly, it can be concluded thatthe more oxygen in the air, the more glycolic acid is formed. This provides greater intensity of light respiration. As a result, a greater amount of carbon dioxide is released into the medium. Scientists suggest that plants developed the ability to regulate light respiration according to the level of carbon dioxide in the air. Organisms not only absorbed oxygen from the environment, which was detrimental to photosynthetics, but also released carbon dioxide, which they needed.

Experiments

You can see in practice how plants breathe.Grade 6 school curriculum in biology covers this issue in great detail. To observe the process, you can take a sheet of indoor 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 process, but also to identify the sample's need for oxygen. On the cut sheet you can see small holes. A part of the sample is immersed in water, with the release of bubbles. There is another way to see how plants breathe. To do this, take a bottle, pour water into it, leaving about two to three centimeters unfilled. The leaf on the long stalk is inserted so that its tip plunges into the liquid. The opening of the bottle tightly plastered with clay (instead of cork). It makes a hole for the straw, which is inserted so that it does not touch the water. Through a straw should be sucked out of the bottle air. From the stem, immersed in water, bubbles will start to stand out.