They are in the air we breathe . . . In our food . . . On our skin . . .
-on everything we touch.
They are . . .
What are microorganisms? (also called microbes)
Microbes are small living plants or animals most of which are not visible to the naked eye. Some microbes cause disease or infection . Many microbes are “good” organisms that help keep balance in the environment and the body.
What microbes lack in size, they make up in number. On the average human, there are about 100 trillion microbes .
Good vs. Bad Microorganisms: Microorganisms that cause disease (germs) are referred to as pathogens . Yeah, I’m bad.
Microorganisms that are harmless or beneficial are called nonpathogens .
Most microbes are considered beneficial or harmless. 87% beneficial organisms 10% opportunists Pathogens 3%
The role of good microorganisms Marine & freshwater microbes form the basis of the food chain in oceans, lakes, and rivers.
Soil microbes help break down wastes .
Humans and other animals depend on bacteria in their intestines for digestion and synthesis of vitamins including: vitamin B (for metabolism) vitamin K (for blood clotting)
Microorganisms have many commercial applications They are used in synthesis of chemical products such as: acetone enzymes alcohol organic acids many drugs
They are used in the food industry for producing: vinegar pickles cheese green olives alcoholic beverages yogurt bread
Main Classes of Pathogenic Organisms:
simple one-celled organisms
At home within “climate” of human body
compose largest group of pathogens
Fungi: yeasts & molds
Plant-like organisms that live on dead organic matter
Grow best in dark, damp places
3) Viruses - smallest microbes
acellular particles (not a complete cell)
one-celled animals often found in decayed materials & contaminated water
caused by larval & egg infestations
Impetigo highly contagious bacterial infection
Extensive case of impetigo on underarm of baby.
Fetal Tetanus (note severe muscle contractions) Due to toxin production as a result of bacterial infection.
Diphtheria Note swelling in neck
Cellulitis An acute bacterial inflammation of connective tissue.
Lymes Disease hallmark “bulls-eye” lesion
Tiny deer tick vector that transmits lymes disease.
Candidiasis: Oral Thrush
Oral Thrush: tongue
Candidiasis of Skin Typical red, slightly most lesions.