Microorganisms What are they? What do they do? What do they look like?
Microbiology • Study of microorganisms • Organisms not visible with naked eye • Require magnifying glass or microscope • Includes wide variety of different organisms
Microorganisms are: • Bacteria • Viruses • Fungi • Protozoa • Animals
Microorganisms are Ubiquitous • Found virtually everywhere • Most are harmless • Some are beneficial • Used in research • Used to make foods (yeast, mold) • Used to make antibiotics
Bacteria • Prokaryoticcells • The genetic material in their cells is not contained in a nucleus • Appear as different shapes • Bacilli (rod-shaped) • Cocci (round) • Spirilla (spiral) • Most ubiquitous microorganism
Bacteria Basic Shapes Cocci (Spherical-shaped) Bacilli (rod-shaped) Spiral-Shaped
Usefulness of Bacteria • Decomposers: (“nature’s recyclers”) break down dead matter • Clean up the Earth’s land & water • Help with digestion • Make vitamins your body needs • Used to make medicines (insulin) • Food production: cheese, yogurt, sour cream, sauerkraut, pickles, etc.
Viruses • Tiny, nonliving particle that enters and then reproduces inside a living cell • Most are harmful
Characteristics of Viruses • Does not have all the characteristics essential for life • Viruses can only multiply when they are inside a living cell • Acts like a parasite • Parasite: an organism that lives on or in a host and causes it harm • Host: an organism that provides a source of energy for a virus
Usefulness of Viruses • Gene Therapy • Take advantage of a virus’s ability to enter a host cell • Gene therapy allows scientists to deliver needed genetic material to cells
Pathogenic Microorganisms • Are harmful to humans • Able to cause pathology (damage) in host - Invade host and damage tissue • Cause infectious disease • Disease that is transmitted from one source to another • Bacteria and viruses responsible for most infectious diseases
Infectious Diseases • Can spread through contact with: • An infected person (touching, hugging, or kissing) • A contaminated object (sharing drinks or eating utensils) • An infected animal (an animal bite) • An environmental source (eating uncooked eggs or meat)
Common Infectious Diseases • Bacterial • Lyme Disease • Tuberculosis • Tetanus • Strep Throat • Viral • The cold • The flu • Cold sores • Chicken pox • AIDS
Treating Infectious Diseases • Bacterial Diseases • Antibiotics: a chemical that can kill bacteria without harming a person’s cells • Antibiotic resistance • Results when some bacteria are able to survive in the presence of an antibiotic • Viral Diseases: No medications that can cure viral infections
Vaccines • Important tools that help prevent the spread of infectious diseases • Vaccine: a substance introduced into the body to stimulate the production of chemicals that destroy specific viruses or bacteria • Made from dead or weak or altered viruses and bacteria