Bacteria (Bacteria, Sing. Bacterium)

Bacteria are microorganisms that are different from animal and plant cells. They do not have a distinct nuclear membrane, which makes them more primitive. Bacteria have a unique composition of cell walls, which is associated with the action of many antibiotics. Most bacteria are unicellular. They may take the form of cocci, bacilli, spirilla, vibrios or spirochetes. The size of bacteria usually ranges from 0.5 to 6 microns. Motile bacteria have one or more thin flagella for movement. Many bacteria also have a capsule - a thick layer of hydrated substance that protects them from external influences. Some bacteria can also form dormant forms under unfavorable conditions. This allows them to remain viable and continue to reproduce even in unfavorable conditions.

Bacteria are microorganisms that do not have a clearly defined nuclear membrane, which makes them more primitive compared to animal and plant cells. In addition, their cell walls have a unique composition that makes them vulnerable to the action of many antibiotics. Most bacteria are single-celled, but they can take on different shapes, such as cocci (spherical), bacilli (rod-shaped), spirilla (spiral-shaped), vibrio (comma-shaped) and spirochetes (helical). The size of bacteria can vary from 0.5 to 6 micrometers, and motile individuals have one or more thin flagella that help them move. Some bacteria may also have a capsule, which is a thick layer of hydrated tissue, and under unfavorable conditions they can form dormant forms that remain viable for a long time.

Bacteria are one of the most numerous and diverse representatives of the living world on our planet. Microorganisms that have the shape of long and thin rods (their length can reach several centimeters and their width can reach tenths of a micrometer) belong specifically to bacteria. These living organisms are the element of the most ancient sphere of our life, thanks to which our world is so diverse and colorful.

Bacteria are less developed in structure compared to animal and plant cells, which is why they are often called primitive. This is due to the fact that the microflora of the body of bacteria is absent, in particular the nucleus. But it is worth noting that over time, a transition to a more complex division system - the nucleoid - began to be observed. This is a very simplified form of the nucleus, which includes only DNA and a small amount of proteins.

Biologists call bacteria prokaryotes, which means that, in addition to the enormous similarity in organizational format, they are also distinguished by its simplified appearance. The structure of a bacterial cell is highly diverse, which is due to differences in the structure of genes. It is worth noting that if we evaluate the structural features of the cell, then bacteria are very similar to eukaryotes. Some microorganisms are characterized by the presence of extremely small organelles called ribosomes, on which the protein structure of the cell is “based”. Another feature of the bacterial cell is the development and death of plasmids. The latter are mobile elements with the help of which it is possible to carry out the transfer of hereditary material. In addition to all this, we can highlight the fact that such a cell does not have mechanical strength, because this element is supported by collagen. The cells of such cultures always tend to take the shape of a ball.

Also, for example, a distinctive feature is the absence of separation into the nucleus and cytoplasm. The entire cell always contains contents called protoplasm. Proof of this fact is the absence of vacuoles in the cell structure. In addition, bacteria are affected by a variety of forms of microorganisms, among them you can find:

- cocci (spherical); - bacilli (bacillus); - spirilla (rod-shaped species with many curls); - vibrios (twisting type); - rickettsia (especially small cocci);

Another object confirming this fact is the features of cell walls. They do not have such a complex composition as that of plants, against the background of which their primitive structure becomes clear. If we judge the components, then their basis is proteins and peptides. We must not forget about one amazing property of bacteria, which is the development of the immune system (antibiotics), the main task of which is to suppress bacteria. Thanks to this property, the creation of bacteriophages became possible. The latter is a special type of virus that “loves” this environmental