Kids Research Express

Bacteria is a one-celled organisms visible only through a microscope. Bacteria live all around us and within us. The air is filled with bacteria, and they have even entered outer space in spacecraft. Bacteria live in the deepest parts of the ocean and deep within Earth. They are in the soil, in our food, and on plants and animals. Even our bodies are home to many different kinds of bacteria. Our lives are closely intertwined with theirs, and the health of our planet depends very much on their activities. Bacterial cells are so small that scientists measure them in units called micrometers (µm). One micrometer equals a millionth of a meter (0.0000001 m or about 0.000039 in), and an average bacterium is about one micrometer long. Hundreds of thousands of bacteria would fit on a rounded dot made by a pencil. Bacteria lack a true nucleus, a feature that distinguishes them from plant and animal cells. In plants and animals the saclike nucleus carries genetic material in the form of deoxyrib...

Staphylococcus, genus of round, parasitic bacteria , commonly found in air and water and on the skin and upper part of the human pharynx. These bacteria are known to cause pneumonia and septicemia as well as boils and kidney and wound infections (see Abscess ; Carbuncle ; Infection ). The antibiotic drug penicillin was once effective for the treatment and control of staphylococci, but the increase of resistant strains requires use of other antiobiotic agents such as semi-synthetic penicillins, cephalosporins or vancomycin. Two common species of Staphylococcus include Staphylococcus aureus, which is commonly responsible for skin infections, and Staphylococcus epidermis, which does not normally cause infection. However, either of these bacteria can cause serious infections under the right conditions. S. aureus is found on the skin and in the nostrils of many healthy individuals. These bacteria often give rise to minor superficial diseases, including the formation of pustules or boils ...