It was established that the biochemical reactions taking place in the human and animal body are the same. Do plants breathe? In the course of many experiments, scientists gave a positive answer to this question.
Oxygen is necessary for the oxidation of organic substances. In this case, the release of energy, which is contained in the molecules, occurs. But if a person has a mouth, lungs, nose through which oxygen enters the body, how do plants breathe? More on 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 have 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 found out how plants breathe, was an experiment with beets and cabbage. At 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 O 2 was
21% Lighting of those and others was carried out around the clock. It was assumed that the plants placed in the chamber would die without oxygen. However, six days later, their weight was significantly higher than those that remained in the air. How do plants breathe without oxygen? About it 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 it comes to darkness, there is in some way a "switch" from one source to another. How do plants breathe in the light and in the dark? Upon receipt of solar energy, the synthesis of organic substances occurs. When dark, the process of oxidation of compounds occurs. In the latter case, they speak of "dark" breathing, and in the first, they speak of "light" breathing. The ability to such a switch allows you to save internal energy reserves. But representatives of the flora breathe in the light, but this process does not bring them any benefit. Absorbing oxygen, plants emit carbon dioxide. It is their main food. In this regard, growth is somewhat slowing. However, there are such representatives of the flora, to whom the light does not interfere with development. Light breathing, for example, is not found in sugarcane and corn.
Causes of light breathing
The beginning, as scientists suggest, was the symbiosis of primitive organisms with non-photosynthetic organisms. Symbiosis is understood as mutual participation in processes that is useful to both parties. Small photosynthetics living in water absorbed carbon dioxide from the environment, releasing oxygen. If there were no breathing, absorbing
2 organisms in the medium, then unbearable conditions would be created for photosynthetics. But in the process of evolution, those representatives of the organic world who were somewhat useful for non-photosynthetics also survived.
One of the compounds that forms during photosynthesis is glycolic acid. This substance is also released by some modern algae. As a result, nephrosynthetics obtained glycolic acid from photosynthetics. This, in turn, contributed to increased oxygen consumption for oxidation of the compound.
Output
Glycolic acid is the very substance that oxidizes and forms carbon dioxide during several biochemical reactions.
Accordingly, we can conclude that the more oxygen in the air, the more glycolic acid is formed. This provides a greater intensity of light respiration. As a result, a greater amount of carbon dioxide is released into the medium. Scientists suggest that a similar principle was developed in plants and the ability to regulate light respiration in accordance with the level of carbon dioxide in the air. Organisms not only absorbed oxygen from the environment, which is detrimental to photosynthetics, but also released the carbon dioxide that they needed.
The experiments
You can see in practice how plants breathe. The 6th grade of the biology school curriculum covers this issue in great detail. To observe the process, you can take a sheet of indoor flower. In addition, you need a magnifier, 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 oxygen demand of the sample. On the cut sheet, you can see small holes. Part of the sample is immersed in water, while the release of bubbles is noted. There is another way to see how plants breathe. To do this, take a bottle, pour water into it, leaving it empty for about two to three centimeters. A leaf on a long stalk is inserted so that its tip is immersed in 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 a straw, air should be sucked out of the bottle. From the stem, immersed in water, bubbles begin to stand out.