What is the oldest thing in the world? It is estimated that many people will not hesitate to say: "bacteria.". The bacteria are small and cannot even be seen by the human eye, and can only be seen through a microscope. So for bacteria, can they see humans again? What do humans look like in their eyes?
Bacteria are the oldest creatures in the world, and they are very small in size. Of the known bacteria, the smallest bacteria are only 0.2 microns long. Bacteria are a type of prokaryote that belong to a single cell.
Another class of archaea is also included in prokaryotes. Compared with eubacteria, the living environment, nutrition and genetics of archaea are fundamentally different from it. In general, whether it is archaea or eubacterium, as members of the bacterial family, their shapes are diverse, but most of them are mainly spherical and spiral-shaped.
Compared to other biological structures, the structure of bacteria is extremely simple, of which bacilli and cocci and spirulina are the most common. Bacteria can not only coexist with other organisms, but also spread in soil and water. There are many bacteria in the human body, such as the gut bacteria that provide the body with the indispensable vitamin B12, which release a large amount of protein when they die, and these proteins will be broken down by the body into the amino acids needed.
Because bacteria parasitize the human body, they can enhance the body's immune function and promote human digestion, so for humans, there is no need to worry about the bacteria present in the body. However, it is worth mentioning that when the human body is affected by external factors and some other bacteria in the body are "activated", it will cause physical discomfort. Bacteria have been on this earth for 3.4 billion years, while humans have only been on this earth for 7 million years. Therefore, there are bacteria in all parts of the human body, but we can't see them with the naked eye.
We humans can't see the bacteria, will they have vision? In fact, not all bacteria are visual, cyanobacteria belong to prokaryotes, it is simple in structure, although it does not have long eyes, but has "vision". It has existed on Earth for nearly 3 billion years, and for humans, cyanobacteria is a beneficial bacterium that does not compete for food and is able to produce chemicals.
Cyanobacteria's vision can distinguish the light source, where there is light, it will move to where. They are the first photosynthetic oxygen-releasing organisms that stabilize nitrogen in the atmosphere and improve soil fertility. Although cyanobacteria are visual, the images they see are upside down, which is not the same as the images they see in reality. For example, when cyanobacteria sees us humans, in its eyes, we humans are head down and feet up. Because cyanobacteria lack the function of our brains that can flip images over, everything they see is upside down.
Except for cyanobacterial bacteria, other bacteria cannot be imaged although they have vision to perceive the presence of light. That is to say, in the case of sufficient light, they will detect the heat emitted by the human body and know the existence of the human body, but they are vague about what humans look like.
Miasmas, plagues, etc. that have appeared in history are actually microorganisms. When Leeuwenhoek invented the microscope, he slowly introduced this thing into the realm of science, and it was not until Koch and Pasteur studied it in depth that they learned that microbial bacteria were the source of infection, followed by the birth of antibiotics.
After so many years of fighting against microbial bacteria, humans thought they had won, but in fact, in the end, after these microbial bacteria continued to upgrade and become stronger, they were all resistant! It turns out that in front of bacteria, humans are small, and it will completely kill a person in minutes. For example, an adult who weighs more than 100 pounds has about 6 pounds of bacteria in his stomach, and these bacteria can have more than 1,000 kinds, and each bacterium is different.
Usually, bacteria live in communities, and they are selfless. If a bacterium develops resistance, it passes the resistance gene to other bacteria in the form of a command. Even bacteria that are not of the same family, after receiving such instructions, will be packed into the genome, and all bacteria in the entire human body will develop drug resistance. After all, it seems that bacteria are a planet-like whole!
Many people often hear things like, "You and your husband are too husband and wife." "In fact, the husband and wife phase is also the credit of bacteria. For example, during the kissing process, the husband and wife will produce nearly 80 million bacteria exchange. After the flora begins to converge, slowly the couple will look particularly similar.
On Earth, bacteria control everything, and humans are not the kings of the earth, but the real kings of microbes. Bacteria control what humans want to eat. Some people like to eat spicy, it can be said that there is no spicy and no joy, in fact, it is not that she likes to eat spicy, but the bacteria in her stomach like to eat spicy. For example, when you were very young, living by the sea, eating seafood every day, a lot of purines, etc., every time you eat seafood, you feel very cool, but in fact, the bacteria in your stomach want to eat seafood, it feels very cool to eat seafood.
The bacteria present in your body will provide you with very good hormones, also known as hormone induction. When you leave the seaside city one day and go to the Northwest Territories. After contacting pasta every day without the pleasure of seafood, the bacteria in your stomach will not adapt, and if you do not grow well, it will cause your intestines to become inflamed, which will eventually cause intestinal flora imbalance.
Overall, the relationship between bacteria and us humans is complementary, and although we can't see bacteria with the naked eye, bacteria know us very well and see us. Even if we have already invented antibiotics and found a way to deal with bacteria, but with the widespread use of clinical practice, today's antibiotics have long been difficult to use for bacteria, super powerful bacteria have developed drug resistance, genetic mutations have occurred, so in front of bacteria, humans are small, and if the human body leaves some bacteria, such as bifidobacteria and lactobacillus that are beneficial to the human body, it is completely impossible to survive. But for bacteria, humans are just one of its many hosts.