The difference between plants and animals is not qualitative, but quantitative. That is, it is expressed in the fact that certain structural features of various organisms predominate. You can not talk about their exceptional property to plants or animals.
Body structure
In the structure of the body, there is a similarity and difference between animals and plants. What do they consist of? There are similarities between plant and animal cells . Lower plants and animals are made up of simple cells. However, they are often mobile. The similarities and differences between plant and animal cells require detailed consideration. We suggest delving into this issue.
Cell structure
The fact that there is a similarity between them is the result of a common origin of life. Both animal and plant cells have the following properties: they are alive, divide, grow, they metabolize. In the cells of both organisms there is a cytoplasm, nucleus, mitochondria, endoplasmic reticulum, Golgi apparatus, ribosomes.
As for the differences, they appeared as a result of different developmental paths, divergences in nutrition, and also the appearance of the possibility for animals to move independently, in contrast to plants. The latter have a cell wall, it consists of cellulose. In animals, it is not observed. The function of the cell wall is that it gives extra rigidity to plants, and also protects these organisms from water loss. Animals do not have a vacuole, but plants have it. Chloroplasts are available exclusively from representatives of the plant kingdom. Inorganic organic substances are formed from them, and energy is absorbed. Animals eat ready-made organic substances. They get them with food.
Animal and plant development
Multicellular animals have an important feature. It consists in the fact that the body of these organisms is equipped with many cavities. They can be considered as a result of the fact that the covers were screwed inside the body of the animal. Most of these cavities are formed that way. Sometimes they appear as a result of the splitting of tissues that form the body of the animal. Thus, the development of the animal can be reduced to the appearance of a number of folds, as well as bends inside the body. As for multicellular plants, in this sense they are devoid of cavities. If they have blood vessels, then they are formed by perforation and fusion of rows of cells. However, the development of plants boils down to the fact that they form protrusions outside the dense primordium. This leads to the fact that various appendages of the body appear, such as roots, leaves, etc.
Mobility
Similarities and differences between animals and plants are also observed in mobility. Animals have greater mobility. Because of this, their cells are mostly bare.
In sedentary plants, as we have already said, they are dressed in a dense shell. It consists of cellulose (fiber). Irritability and mobility are not exclusive properties of animals. However, these features they still achieve higher development. Nevertheless, not only unicellular, but also multicellular plants are mobile. There is a similarity between unicellular plants and animals or the embryonic stages of multicellular organisms even in the way they use movement methods. Both are characteristic of those that are carried out by inconsistent processes, otherwise called pseudopodia. This is called an amoeboid movement. The similarity between plants and animals is that both can move using harnesses.
They can also do this by releasing substances from their body. These secretions allow the body to move in the right direction, the opposite direction of the outflow of matter. In particular, diatoms and gregarins possess this property. Multicellular higher plants turn leaves to light in a certain way. Some of them stack them overnight. In this case, we can talk about the phenomena of the so-called plant sleep. Some species are able to respond with movements to touch, shake and other irritations.
These features of similarity of animals and plants are very interesting. However, many others are no less curious. We invite you to learn about them.
Separation of muscle and nerve tissue
The following similarities and differences between animals and plants are associated with muscle and nervous tissue. Charles Darwin showed that the tips of the roots and stems of all plants rotate. However, only in multicellular animals there is isolation as a separate tissue of contractile muscle, which performs the function of irritability, as well as isolation of special sensory organs, which serve to perceive various irritations. But even among multicellular animals there are species that do not have separate nervous and muscle tissue, as well as sensory organs. This, for example, some sponges.
Plant nutrition method
In nutrition, there is also a similarity and difference between animals and plants. However, there is still more certainty. It is believed that the main difference between plants and animals comes down to their type of nutrition. Plants using chlorophyll (green pigment) form organic matter from oxygen, carbon and hydrogen, which they find in water and in the air. This creates fiber, starch, and other nitrogen-free substances. And by adding nitrogen, which is found in the soil in the form of nitrogenous salts, the plant also builds protein substances. Thus, these organisms are able to find food everywhere. In plant life, movement cannot play such a large role as in animals.
The way to feed animals
These organisms can exist only due to the organic compounds presented in finished form. They receive them either from plants or from other animals, that is, ultimately from plants.
The animal must be able to get its own food. It is from here that his great mobility flows. The plant forms organic compounds, while the animal destroys them. It burns these compounds in its body. As a result of this process, decay products in the form of urine and carbon dioxide are released. The animal constantly releases carbonic acid from the atmosphere back into the atmosphere. During its lifetime, it releases nitrogen through urination, and after death, during decomposition. The plant takes carbonic acid from the atmosphere. Nitrogenic bacteria translate nitrogen into the soil. From it, it is again consumed by plants.
Breathing features
The similarities and differences between animals and plants also apply to respiration. Regarding the fact that is accompanied by the release of carbon dioxide and the absorption of oxygen, we can say that it is equally characteristic of both plants and animals. However, the latter, this process is much more energetic.
In plants, such breathing is noticeable only when the nutrition process, the opposite of this process, is not completed. Nutrition is the absorption of carbon dioxide, in which part of the oxygen is released into the atmosphere. It may not occur, for example, during seed germination or in the dark.
Since the combustion process in animals is more energetic, the temperature increase in them is more noticeable and stronger than in plants. Thus, respiration in plants still exists, however, the main role of these organisms in the circulation of substances is to absorb carbon dioxide, release oxygen, and also consume nitrogen in the atmosphere (with the help of bacteria). In animals, the opposite role. They produce carbon dioxide and nitrogen into the atmosphere (also partially with the help of bacteria during rotting), and they absorb oxygen.
Nutrition: exceptions to the rules
Often there is a similarity of plants and animals in the way they feed. For example, chlorophyll-free mushrooms use ready-made organic substances for food. And some flagella and bacteria can create organic matter, while they are devoid of chlorophyll. A number of insectivorous plants are able to capture and process animal tissue. Thus, the similarity of plants and animals is manifested. Some types of flagella, which contain chlorophyll, produce in the light of the grain, in their properties similar to starch. So, they feed in the same way as plants. And in the dark, their nutrition occurs saprophytically, that is, it is carried out by the entire surface of the body due to decomposing substances.
Atypical chemical composition of elements
The similarity of plants and animals is also observed in the chemical composition of the elements of which their bodies are composed. True chlorophyll, however, is characteristic only of plants. In some cases, it can be found in the body of higher animals. However, it does not belong to them, but to algae. Some of them live symbiotic in the body of animals. We already know that many plants lack chlorophyll. On the other hand, Euglena, which has an active chlorophyll, and other forms like it, have almost the same right to be assigned to the animal kingdom as to the vegetable one. To date, there is no evidence of similarity with chlorophyll of the green pigment found in the wings of Orthoptera. This pigment, in any case, does not function as chlorophyll in them.
Related Substances
The similarity of plants and animals is manifested in similar substances present in their bodies. The former is characterized by the presence of fiber. However, the shell encircling the bodies of a number of marine animals consists of tunicin. This substance is similar to fiber. For plants, as you know, a substance such as starch is characteristic. However, in the life of animals, its isomer (glycogen) plays an equally important role. And in myxomycetes, or mucous membranes, instead of starch there is just glycogen.
Output
All of the above leads us to the conclusion that the differences between plants and animals are rather arbitrary. We can conclude that both come from a common source, that is, from such forms that can rightfully be attributed to both plants and animals. These forms are partially preserved on our planet.