Microorganisms make up much of the planet's living matter and play an important role in maintaining the Earth's ecosystem. Microorganisms are small organisms that cannot be seen with the naked eye. They are microscopic and are generally known to cause disease in animals and humans. A microorganism is a microscopic living organism, which can be unicellular or multicellular, and the study of microorganisms is known as microbiology. (Campbell et al., n.d.) Say no to plagiarism. Get a tailor-made essay on "Why Violent Video Games Shouldn't Be Banned"? Get Original Essay Microorganisms have a great impact on human life and are used for various purposes and participate in various cycles. Bacteria are critical to the nitrogen cycle. There are four main parts of the nitrogen cycle, and bacteria play a role in each of them. Nitrogen gas is converted into nitrate compounds by nitrogen-fixing bacteria in the soil or root nodules. Lightning also converts nitrogen gas into nitrate compounds. The Haber process converts nitrogen gas into ammonia used in fertilizers. Ammonia is converted to nitrates by nitrifying bacteria in the soil. Plants absorb nitrates from the soil and use them to build proteins. The plant can be eaten by an animal, and its biomass can be used to produce animal protein. Urea and egested material are broken down by decomposers. This causes the nitrogen to be returned to the soil in the form of ammonia. Decomposers also break down the bodies of dead organisms resulting in nitrogen being returned to the soil in the form of ammonia. Under some conditions, denitrifying bacteria in the soil break down nitrates and return nitrogen to the air. This is usually in waterlogged soil. Improving drainage reduces this effect, making the soil more fertile. (Mary Jones, 2008) The production of many foods is possible with the help of microorganisms. For example, foods such as bread, beer and cheese are produced with the help of yeast. Likewise, bacteria are involved in the production of butter, yogurt, many types of chocolate, coffee and other foods of daily life. It is very difficult to decode the human genome if disorders occur in it since humans are eukaryotic organisms. It means that their body is made up of various types of cells and they are all differentiated into different tissues and organs. Microorganisms have made it possible to produce drugs that, when they enter the body, target faulty genes and make healthy changes in them, making them functional again. There is a common example of human insulin. Insulin is an antibiotic prescribed to diabetic patients. It is now possible to synthesize insulin in microorganisms such as bacteria and yeast. These microorganisms are inserted into the body in the form of vectors and cure the defective genes. (Campbell et al., n.d.)Our body contains ten times more microorganisms than cells in the body. These microorganisms are useful for the organism and perform various useful functions, for example E. coli (bacteria species) resides in the intestine and releases components that help in the digestion of food. One of the purposes of bacteria in the body is to fight harmful bacteria that can cause disease. For example, in the intestine there is also a bacterium that helps synthesize vitamins such as biotin, vitamin K and folic acid. Biotechnology is one of the fields that has mostly used microorganisms. Using the techniques of biotechnology, scientists have managed to develop human growth, growth hormones and other useful components of the body. Biotechnological processes use microorganisms for drug delivery underform of vectors and plasmids. Microorganisms have provided many benefits to agriculture as they are responsible for increasing soil fertility. Thanks to this, plant production increases and the economy becomes strong. (Pete Kennedy, 2009). Bacteria present in the environment are responsible for recycling waste and producing energy sources such as carbon and nitrogen. Plants use carbon dioxide during the process of photosynthesis. More carbon dioxide consumption will lead to more food production. Some bacteria also help clean the environment by digesting pollutants and as a result release environmentally friendly nutrients. (Mary Jones, 2008) Microorganisms are widespread in nature and are beneficial to life, but some can cause serious harm. They can be divided into six main types: bacteria, archaea, fungi, protozoa, algae and viruses. Bacteria are single-celled organisms. The cells are called prokaryotes because they have no nucleus. They exist in four main forms: bacillus (rod shape), coccus (spherical shape), spirillum (spiral shape) and vibrio (curved shape). Most bacteria have a peptidoglycan cell wall; they divide by binary fission; and may possess flagella for motility. The difference in cell wall structure is an important feature used in the classification of these organisms. Depending on how the structure of their cell wall is deformed, bacteria can be classified as Gram-positive or Gram-negative when using the Gram stain. Bacteria can be further divided based on their response to oxygen gas into the following groups: aerobic (living in the presence of oxygen), anaerobic (living without oxygen), and facultative anaerobic (can live in both environments). (Campbell et al., n.d.) Archaea or archaea differ from true bacteria in cell wall structure and lack peptidoglycans. They are prokaryotic cells with avidity towards extreme environmental conditions. Based on their habitat, all Archaeans can be divided into the following groups: methanogens (organisms that produce methane), halophiles (Archaea living in salty environments), thermophiles (Archaea living at extremely hot temperatures and phycophiles (Archaea living at cold temperatures).The Archeans use different energy sources such as hydrogen, carbon dioxide and sulfur. Some of them use sunlight to produce energy, but not in the same way as they absorb sunlight using their pigment. membrane, bacteriorhodopsin formation of the energy molecule adenosine triphosphate (ATP) (Pete Kennedy, 2009). Some examples of fungi are molds that show thread-like (filamentous) growth and multicellular structures, yeasts that are typically non-filamentous and can be unicellular. and fungi that possess a fruiting body for spore production have been used to make pharmaceutical products, including penicillin, which is one of the most commonly prescribed antibiotics, and cyclosporine, used to prevent organ rejection after a transplant. Fungi are eukaryotic cells (with a true nucleus). Most fungi are multicellular and their cell wall is composed of chitin. They obtain nutrients by absorbing organic material from their environment (decomposers), through symbiotic relationships with plants (symbionts), or harmful relationships with a host (parasites). They form characteristic stringy tubes called hyphae that help absorb material. The set of hyphae is called mycelium. Mushrooms reproduce by releasing spores. (Mary Jones, 2008) Protozoa are single-celled aerobic eukaryotes. They have a nucleus, complex organelles and obtain nutrition by absorption or ingestion through.)