Lesson 5: “Microorganisms and Disease” What are microorganisms? Microorganims are organisms that are microscopic or too small to be seen with just the eyes. They can be unicellular or multicellular. Microorganisms include bacteria, viruses, protists, and fungi.

Lesson 5: “Microorganisms and Disease” How can microorganisms be harmful? A disease is anything that interferes with the normal functions of the body. Disease causing agents are called pathogens. An infectious disease is caused when pathogens are passed from one organism to another. Pathogens can be transmitted in three ways… 1. through direct contact with an infected individual 2. through the air 3. by touching a contaminated object ****Animals can also pass pathogens to people.

Lesson 5: “Microorganisms and Disease” How can microorganisms be harmful? (continued) Below is a list of bacteria / diseases that are caused by harmful bacteria… 1. strep throat 2. scarlet fever 3. tetanus 4. E. coli 5. Salmonella 6. Lyme disease

Lesson 5: “Microorganisms and Disease” How can microorganisms be harmful? (continued) Below is a list of diseases that are caused by harmful fungi and protists. 1. athlete’s foot 2. dysentery 3. sleeping sickness 4. malaria 5. potato blight

Lesson 5: “Microorganisms and Disease” How do we protect ourselves from harmful microorganisms? The process of pasteurization destroys harmful bacteria in liquids such as milk by heating it to a high temperature. Cooking food also destroys many harmful bacteria. Antibiotics are chemical used to treat bacterial infections. A vaccine made from dead or weakened pathogens can prevent you from getting certain diseases. The best way to stop the spread of most infectious diseases is to wash your hands.

Lesson 5: “Microorganisms and Disease” How do we protect ourselves from harmful microorganisms? (continued) Important people in the area of microbiology… Edward Jenner - created the first vaccine ever / prevented spread of small pox Louis Pasteur – created the process of pasteurization to kill bacteria in liquids such as milk Alexander Fleming – created the first antibiotic Jonas Salk – created a vaccine to prevent polio