Bacteria describes a large group of microorganisms. Prokaryotes is a domain that consists organisms without a membrane bound nucleus and covers both bacteria and archaeia. Bacteria are usually a few micrometers and cannot be seen by the naked eye. They exist in almost every climate and source from hot springs to the Arctic circle. Their shapes vary from circular to rod-shaped and even spirals.
Although bacteria are often associated with germs and sickness, they serve an essential function. They perform vital tasks such as recycling nutrients. Nitrogen fixation is accomplished by bacteria living in the soil and around the roots of plants. Also, bacteria help to break down waste. A pile of rotting leaves may not seem appealing, but the bacteria that perform the breakdown are beneficial, turning the leaves into a mulch that will provide nutrients to the plants as well as reducing the waste that humans and animals generate.
In addition to bacteria living on different surfaces, the human body itself is highly colonized with bacteria known as normal flora. Most of these bacteria are harmless and even provide essential nutrients. Staphylococcus epidermidis is a bacteria commonly found on skin. In rare cases, it can cause disease, but usually exists peacefully on the human body and even prevents other bacteria from causing disease. In the large intestine, E. coli are found, which provide vitamin K, essential for the clotting function of blood. Knowing the positive aspects of bacteria is just as important as recognizing the pathogenic traits.
Some bacteria can be harmful and even deadly. Staphylococcus can cause pneumonia and meningitis. These diseases can be life-threatening, especially if not treated promptly with antibiotics. Lyme disease is also caused by bacteria carried by the common tick. Often not diagnosed correctly, it can cause chronic arthritis and provide life-long pain. Many sexually transmitted diseases are also caused by bacteria. Chlamydia is a common sexually transmitted disease that is easily spread during intercourse and caused by bacteria.
Not all bacteria is harmful though. Yeast is an example of bacteria that provides many beneficial affects to everyday life. It contributes to the leavening of bread and the fermentation of products such as cheese, yogurt, and wine. Biotechnology studies and uses bacteria to treat diseases. Bacteria, because of their simple cellular structure, can often be modified to perform certain functions in the body. The study of bacteria is immense and well-worth the time.