Microbes Page 81 in your Lab Book
Microbes Microbes are living organisms that are too tiny to be seen with the naked eye Microbes live in the water you drink, the food you eat, and the air you breathe Most microbes are helpful, like intestinal microbes which help humans digest food Microbes that cause disease are called pathogens
PROTOZOA Made of a single cell that includes a nucleus Many shapes and sizes
Protozoa Can be parasitic, needing to live within another organismparasitic Can be free-living in moist habitats Examples of diseases caused by protozoa: Malaria, African Sleeping Sickness, Amoebic Dysentery
FUNGI Plant-like except no chloroplasts Some get their nutrition by breaking down remains of dead plants and animals (helps recycle the earth) Some are parasitic (ex. Feed on bread – create spores) Examples of diseases caused by fungi: Athlete’s Foot and Ringworm Useful in creating some antibiotics Kill some plants, insects and fish
Fungi
BACTERIA The most common pathogen Made of one cell that does not have a nucleus but does have chromosomes that contain DNA There are three basic shapes Cocci (Sphere) Bacilli (Rod) Spirilla (Spiral)
Cocci (sphere) bacteria
Bacilli (rod) bacteria
Spirilla (spiral) bacteria
Bacteria Some are very helpful. They aid in digestion, help decompose soil, and change milk into cheese.digestion They need food, water, and warm temperatures to live. They can remain dormant until they find the right conditions, then they begin to divide every 20 minutes.
Bacteria Examples of diseases caused by bacteria: Tuberculosis, Strep throat, leprosy, plague, food poisoning, diptheria, Lyme Disease, “the fung” (ask Webber).Tuberculosis, Strep throat, leprosy, plague, food poisoning
VIRUS A virus is not a cell. It has a protein coat and a DNA core. A virus can only be seen under an electron microscope A virus always causes disease.
Virus It invades a cell It takes over the nucleus It begins to replicate, making many viruses The cell membrane bursts More viruses are released to attack other cells Examples of diseases caused by viruses: chicken pox, measles, flu, colds, and polio
PRION Unlike all other microbes, they contain only proteins that allow for replication They are named from proteins and infections Like viruses, they replicate in their host, yet can’t live on their own.
Prions Diseases caused by prions include mad cow disease