1. Microbiology By: Ariel Friedman

2. Microbiology Bacteria are an important group of living organisms. Most of them are microscopic and unicellular, with a relatively simple cell structure, lacking a cell nucleus, and organelles such as mitochondria and chloroplasts.

3. Harmful Bacteria

4. Harmful Microbes Some bacteria are harmful. Harmful Bacteria cause Strep Tetanus Infections Pneumonia

5. Strep Throat Strep throat is caused by streptococcal bacteria.

6. Tetanus Tetanus is caused by Clostridium tetani. There is an immunization for the prevention of tetanus.

7. Infections at scratch disease, a bacterial infection that causes swelling of the lymph nodes, usually is due to the scratch, lick, or bite of a cat — more than 90% of people who contract it had contact with cats or kittens. Bartonella henselae, the bacterium that causes this disease, is found in all parts of the world.

8. Pneumonia Germs called bacteria or viruses usually cause pneumonia.