Bacteria are a group of single-celled, microscopic microorganisms without organized nuclei. They come in a variety of shapes; Some are round, cylindrical or spiral in shape. The number of described species of bacteria is about 15,000. These are all pathogens and the idea that they are always harmful to humans is not correct. Bacteria have a number of beneficial properties. Bacteria are very important in maintaining the balance of living things, and they are essential for the regeneration of living things by melting dead organisms into simple molecules.
The benifits of Bacteria : Bacteria collect enough nitrogen from the air, which various organisms can easily use. In this case, the role of Rhizobium bacteria is important and they can be used in artificial cultivation as a biofertilizer by breeding them. Many species of bacteria (mainly Escherichia coli, Lactobacillus, Streptococcus) live in the human intestine, which provide nutrients and maintain the conditions conducive to normal bowel function
Bacterial disease :Many deadly diseases are caused by bacteria, such as plague , tuberculosis, sexually transmitted diseases, syphilis and gonorrhea, intestinal disorders, cholera, dysentary and typhoid, respiratory diseases, pneumonia, meningitis, etc. Of the numerous bacterial species, only a small number, or less than 5 percent, are pathogens.
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