9781422276150

Bacteria are small one-celled organisms found everywhere in and around our body. They are relatively simple organisms, and are extremely small; a pinhead may have millions of bacteria on it. Under the microscope they may appear as rods (bacilli), sphere (cocci) or spiral (spirilla) shaped. They need food, water, warmth, and time to grow. Types of Bacteria Bacteria are categorized into two types: archaebacteria and eubacteria. Archaebacteria

are those bacteria that survive in extreme conditions, such as in Antarctica or under deep sea. Some examples of archaebacteria are methanogens, thermophiles, and halophiles. Eubacteria reside in human skin and cavities. They can cause soft tissue infections.

WORDS TO UNDERSTAND

budding: a form of asexual reproduction in which an organism reproduces by itself. chemosynthesis: the process in which certain organisms make food without the help of sunlight, using carbon dioxide and water. DNA: deoxyribonucleic acid is a substance containing genetic information and is present in all living organisms. enzymes: a chemical that triggers, or increases the rate of, a reaction. fragmentation: a type of asexual reproduction in which part of an organism if cut can grow into a new organism. nucleic acid: a liquid (in the form of DNA/RNA) that is found in the cells of all living beings.

9