Jennifer Stearns

When you're studying microbiology, you need to know the key differences between the three domains of life, how scientists name and classify organisms, and how scientists identify microorganisms.Differences among bacteria, archaea, and eukaryotic microorganismsThere are three domains of life: bacteria (also known as eubacteria), archaea, and eukarya.

Vaccines have been essential in eradicating or preventing life-altering diseases, but lately, they've come under fire. Here are some common myths about vaccines: Myth 1: Vaccines aren't actually necessary. The truth is that vaccines have been essential to reducing rates of childhood illnesses. Before vaccines, 25 percent of children died before the age of 5 from pneumonia, diarrhea, measles, pertussis, or rubella, among other diseases.

The habitat is an important concept in biology and microbiology in particular because microorganisms are greatly affected by where they live. Microbial habitats — including soils, rivers, lakes, oceans, on the surface of living and dead things, inside other organisms, on man-made structures, and everything in between — provide nutrients and protect cells from harsh conditions.

Unlike the physical requirements where a specific range or concentration is necessary for optimum growth, the chemical requirements just need to be present in the environment and a microbe will use what it needs. Microbes use compounds containing the following elements and vitamins to make everything in the cell including membranes, proteins, and nucleic acids: Carbon: Carbon is necessary for all life.

Since the beginning of their widespread use in 1943, antibiotics have saved countless lives and changed the way medicine is practiced. Before their discovery, people suffered or died from infectious diseases that today are a mere annoyance, like sexually transmitted diseases and post-operative infections. Today antibiotics are essential in treating life-threatening bacterial infections, like pneumonia and sepsis, and are used preventively in a number of medical procedures (like surgery) and treatments (like cystic fibrosis).

To keep the many organisms on earth straight, in the 18th century the Swedish botanist Carl Linnaeus developed a simple nomenclature system to classify and name all organisms including bacteria. This system ranks all organisms using the following headings, shown with the example of the bacterium E. coli. Domain: Bacteria Phylum: Proteobacteria Class: Gammaproteobacteria Order: Enterobacteriales (Order names always end in –iales.

There are three domains of life: Bacteria (also known as Eubacteria), Archaea, and Eukarya. The Bacteria and Archaea are made up entirely of microorganisms; the Eukarya contains plants, animals, and microorganisms such as fungi and protists. The Bacteria and Archaea have been grouped together and called Prokaryotes because of their lack of a nucleus, but the Archaea are more closely related to the Eukaryotes than to the Bacteria.

Microorganisms can't be seen with the naked eye, so they're identified in several indirect ways: Microscopy to identify cell shape or appearance of spores. Cells are often stained to enhance cellular features, and the properties of the cell wall are used in the classification of microorganisms. Appearance of colonies on laboratory media is a widely used method of distinguishing between different microbes, mainly bacteria.