Microbiology Definition and Types of Microorganisms

Study Notes

Study of microorganisms, including bacteria, viruses, fungi, and protists
Microorganisms are typically microscopic, but can also be larger, such as protozoa

Bacteria:
- Prokaryotic cells, lacking a true nucleus
- Typically 0.5-5.0 μm in size
- Can be aerobic or anaerobic
- Examples: E. coli, Staphylococcus aureus
Viruses:
- Not considered living cells, as they require host cells to replicate
- Consist of a protein coat (capsid) and genetic material (DNA or RNA)
- Can infect animals, plants, and bacteria
- Examples: Influenza, HIV
Fungi:
- Eukaryotic cells, with a true nucleus
- Can be unicellular or multicellular
- Examples: Yeast, Mold, Mushrooms
Protists:
- Eukaryotic cells, with a true nucleus
- Typically unicellular, but can be multicellular
- Examples: Protozoa, Algae, Slime molds

Growth:
- Microorganisms can grow rapidly, with some doubling in as little as 20 minutes
- Growth can be measured by turbidity, colony count, or biomass
Nutrition:
- Microorganisms can obtain energy through photosynthesis, respiration, or fermentation
- Nutrient sources include organic compounds, inorganic compounds, and other organisms

Symbiosis:
- Mutualism: both organisms benefit
- Commensalism: one organism benefits, the other is unaffected
- Parasitism: one organism benefits, the other is harmed
Microbial Communities:
- Biofilms: complex communities of microorganisms attached to a surface
- Microbial consortia: groups of microorganisms working together to perform a specific function

Medicine:
- Diagnosis and treatment of infectious diseases
- Development of vaccines and antibiotics
Food and Beverage:
- Fermentation in food production (e.g. yogurt, cheese, bread)
- Spoilage and preservation of food
Environmental Science:
- Bioremediation: using microorganisms to clean up pollutants
- Microbial ecology: studying the role of microorganisms in ecosystems

Study of microorganisms, including bacteria, viruses, fungi, and protists
Microorganisms are typically microscopic, but can also be larger, such as protozoa

Growth
Microorganisms can grow rapidly, with some doubling in as little as 20 minutes
Growth can be measured by turbidity, colony count, or biomass
Nutrition
Microorganisms can obtain energy through photosynthesis, respiration, or fermentation
Nutrient sources include organic compounds, inorganic compounds, and other organisms

Symbiosis
Mutualism: both organisms benefit
Commensalism: one organism benefits, the other is unaffected
Parasitism: one organism benefits, the other is harmed
Microbial Communities
Biofilms: complex communities of microorganisms attached to a surface
Microbial consortia: groups of microorganisms working together to perform a specific function