<h1>Is green animals possible</h1>?
The green animal mentioned here does not refer to the green frog, but to the animal that contains chloroplasts in the cell and can be self-nourished by photosynthesis like green plants. Has anyone ever seen such an animal, at least in a clear-headed situation?
Why there are no green animals, if there is, green animals should be quite good, compared to other animals, green animals do not need to rush for food every day, they can solve it through photosynthesis, while all other animals in existence are in the crisis of food shortage all the time, including us humans. People who can often beg for food along the street will certainly be much happier if they can photosynthesize.
We all know that plants are able to photosynthesize because plants contain chloroplasts, and the role of chloroplasts is to use light energy to process carbon dioxide and water into sugar and release oxygen. But some people may not know that plants can survive because plants contain mitochondria, mitochondria for aerobic respiration, oxidation of sugar and fat to produce energy, providing energy for every cell of the plant and the entire plant, so that plants can survive. The cells of plants contain both chloroplasts and mitochondria.
Now, you probably think that animal cells contain only mitochondria, and can only oxidize substances containing energy to release the energy contained in the substance, but due to the lack of chloroplasts, they cannot directly use light energy to produce substances containing energy, such as sugar and fat, and animals can only obtain these energy substances by eating other animals or plants.
So why can't animal cells contain both chloroplasts and mitochondria? Let's first take a look at what the biggest difference between animals and plants is, apart from containing chloroplasts. Without a doubt, the most obvious difference is that plants are immovable while animals are moving.
We all know that exercise requires more energy. An adult male sitting consumed about 2,000 kcal of energy for a whole day, about 2,600 kcal for a normal day, and about 3,300 kcal for an adult male athlete. In fact, even if a person lies still, his interior is always moving, his heart is beating, his intestines are peristalsis, blood is flowing, and so on. 2000 kcal energy, it sounds like a lot, but in fact it is not much, a pound of rice can almost produce this energy. But the same energy is very difficult to achieve through photosynthesis. The plant known to have the wildest photosynthesis is Chlorella, a single-celled organism that, although containing only one chloroplast, is a giant chloroplast that makes up most of the cell. Chlorella photosynthesis is more than ten times more intense than other plants. One kilogram of chlorella can produce 0.6 grams of glucose in 1 hour, calculated by having 12 hours of light per day, ideally, one kilogram of chlorella can produce 7.2 grams of glucose a day. A full oxidation of one gram of glucose can produce 4 kcal of energy, so that it takes 500 grams of glucose to maintain a person's most basic energy consumption a day. So, let's see how much energy a chlorella as heavy as a person can produce in a day by photosynthesis, if a person is calculated by 65 kg of body weight, the same weight of chlorella can produce 7.2 grams * 65 = 468 grams of glucose in a day, from the results can barely be the same as the basic energy consumption of a person a day. But do not forget, this is an ideal situation, the so-called ideal situation means that each chlorella is flat, can fully feel the sunlight, photosynthesis, if chlorella is somewhat superimposed on each other, then stacked below will not be able to fully photosynthesis, even if considering the light transmittance of the cell, the actual production of glucose can reach one-tenth of the ideal value is good, which is only about 50 grams, far from maintaining a person's most basic energy consumption. Moreover, chlorella is already the most intense plant of photosynthesis in nature, and other plants of the same weight can only produce about 5 grams of glucose in a day, which is unable to meet human energy consumption. This means that even if there is a green human race with chloroplasts in its cells that wants to survive by photosynthesis, he will soon die, because the energy generated by his daily photosynthesis is far from enough to maintain his daily energy expenditure, even if he is motionless.
Although the total amount of light energy projected by the sun on the earth every minute is very large, it is not much specific to a small area. In this regard, we should have some experience, when have you ever seen a solar car run faster than a normal gasoline-burning car, even if the solar car is covered with solar panels larger than its own area.
Animals are highly energy-intensive, even cold-blooded, and their lifestyles and body structures dictate that they must have a more efficient way of obtaining energy than photosynthesis, that is, direct access to energy-rich organic matter. So why don't animals use a dual energy harvesting method, that is, cells contain chloroplasts, can photosynthesis, and can also directly feed on organic matter. The reason is that maintaining two systems at the same time is inefficient, we have seen above, the energy generated by photosynthesis is far from enough for the energy consumption of animals, and in order to be able to photosynthesis, the body structure of animals undoubtedly needs to change in a direction that is not conducive to movement, which will greatly detrimental to this predatory lifestyle as an animal, and directly eating a little organic matter can obtain a lot of energy, therefore, for animals, completely abandon photosynthesis This way of obtaining energy, It is wise and costly to live entirely by relying on direct access to organic matter. Maintaining two sets of opposite and irreconcilable ways of obtaining energy is a very inefficient design. It's an impossible creature to appear. Even if it ever has been, it must have been eliminated by nature because of its lack of competitiveness for survival.
So why can plants survive on photosynthesis alone? Because plants adopt a completely different design from animals, they reduce their energy consumption to the extreme. First of all, the plant is inactive from the outside, and you will never see a plant hurriedly passing in front of your eyes. Not only do plants not do big exercises, plants do not even do small exercises, plants do not shake branches and knock on tree trunks when they are irritable. The interior of the plant is also immovable, the movement in the animal body accounts for most of the energy consumption, in order to transport nutrients to every cell of the body, the animal's heart should beat, the lungs should breathe, the intestines should peristalsis, and the blood should run. The plant cleverly uses the transpiration of water through the small holes in the leaves to automatically transport the nutrients dissolved in the water to each of its cells without any energy consumption. Through such a "immovable" design, plants minimize their own energy consumption, and most plants consume only one-tenth to one-third of the energy they produce every day. The remaining energy is stored for the growth and development of the plant itself, as well as for energy-intensive activities such as flowering and fruiting.
Of course, I admit that not all plants are absolutely immobile, and some parts of plants can indeed be moved, and even moved quite quickly in a short period of time, so fast that they can kill insects. For example, tanuki, flycatcher, thatch, etc., when an insect crashes into the hunting mechanism of such plants, these plants will either quickly close the lid of the bottle, or will quickly close two loose pages with mucus, enclose the insect in it, and then secrete digestive juice to digest the insect. This kind of rapid activity consumes a lot of energy, and photosynthesis alone cannot maintain this activity, which is why these plants hunt protein-rich insects, and they must rely on direct protein consumption to maintain this very crazy life for plants. There is no doubt that if you always touch these carnivorous plants with plastic rods, making their hydraulic motion system overworked and unable to catch anything edible, you will soon starve these plants alive.
So, is there really no green animal in the world? There is absolutely no such green animal in multicellular animals. However, we know that single-celled organisms are a very peculiar class of organisms, they are very simple, so simple that they are made up of only one cell. In this extreme structure, will the impossible become possible? The answer is yes. There is indeed such a single-celled organism, which is the eye worm. The eye worm is arguably the most peculiar animal in the world, it contains chloroplasts, which look like plants, but at the same time the eye worm has a long flagella at the front end of the body, the structure of this flagellar is quite complex, composed of 20 microtubules, containing motor proteins similar to muscle composition, which can swing the flagella to make it swim around. In the case of light, the eye worm relies on photosynthesis to obtain energy, because the eye worm is only a cell, very small, so its movement consumes very little energy, and it can maintain its movement by photosynthesis. In the absence of light, eyeworms can obtain energy by absorbing organic matter dissolved in water on the surface of the body.
Why are there such amazing animals? It is because evolution will try in all possible and impossible directions, and as soon as it starts to try, who can be sure that it must be impossible. Life has gone through billions of years, tasted all the suffering and laughter, and now occupies the six realms of plants, animals, fungi, protists (single-celled eukaryotes), prokaryotes, and non-celled organisms (viruses and viruses), like the six reincarnations in Buddhism. Life has given us so much to learn, and the most important of them is to dare to try.