Micro Test 1 Prep Flashcards

Microbiology Key Figures and Concepts

• Louis Pasteur: Demonstrated ubiquitous microorganisms, disproved Spontaneous Generation, discovered fermentation by yeast, linked spoilage to microbes, developed Pasteurization, rabies vaccine, and invented the swan-neck flask.

• Robert Koch: Pioneer of techniques to isolate pathogens; isolated Bacillus anthracis, tuberculosis bacillus, and Vibrio cholerae. Developed Koch's postulates, awarded Nobel Prize in 1905.

• Carolus Linnaeus: Introduced the system of Binomial Nomenclature for scientific classification in 1735.

• Francesco Redi: Discredited spontaneous generation by demonstrating flies generate maggots on decaying meat in 1668.

• Theodor Escherich: Discovered Escherichia coli, critical in understanding gut microbiota.

• Binomial Nomenclature: Organisms are classified by genus and species, with genus capitalized and both italicized.

• Disinfectants: Phenol (carbolic acid) was the first used widely to reduce infections caused by microorganisms.

• Alexander Fleming: Discovered penicillin in 1928, leading to modern antibiotics.

• Carl R. Woese: Introduced the three-domain system (Archaea, Bacteria, Eukarya) in 1990.

Microbial Classification

• Three Domains: Archaea, Bacteria, and Eukarya; protozoa belong to Eukarya.

• Microorganism Categories: Include Bacteria, Archaea, Fungi, Algae, Protozoa, Helminths, and Viruses.

• Bacteria: Prokaryotic, unicellular, with cell walls made of peptidoglycan.

• Fungi: Eukaryotic, non-tissue forming, spore-reproducing, with cell walls of chitin.

• Algae: Eukaryotic, photosynthetic organisms; part of phytoplankton.

Environmental Microbiology

• Archaea: Prokaryotic, unicellular, can be extremophiles (halophiles, acidophiles, alkaliphiles, hyperthermophiles).

• Microbial Survival: Endospores protect bacteria in harsh conditions; fimbriae facilitate adherence.

Microscopy and Techniques

• Koch's Postulates: Guidelines to establish a causative relationship between a microbe and a disease (isolation, culture, infection, and re-isolation).

• Golden Age of Microbiology (1857-1914): Establishment of germ theory, use of disinfectants, surgical improvements, and vaccination development.

• Gram Stain: Differentiates bacteria into gram-positive (thick peptidoglycan) and gram-negative (outer membrane).

Microbial Structure and Function

• Cellular Structures:

  • Capsule: Gelatinous layer in some bacteria.
  • Fimbriae: Attachment structures on bacteria.
  • Plasmids: Circular DNA in bacteria, contains additional genes.

• Transport Mechanisms:

  • Facilitated Diffusion: Process where glucose crosses cell membranes without energy.
  • Active Transport: Requires energy to transport substances against a gradient.

Taxonomy and Classification Systems

• Five Kingdom System: Proposed by Robert H. Whitaker; includes Prokaryote, Protista, Fungi, Plantae, Animalia.

• Taxonomic Hierarchy: Ranks include Domain, Kingdom, Phylum/Division, Class, Order, Family, Genus, and Species.

Measurements in Microbiology

• Micrometers (um): One millionth of a meter.
• Nanometers (nm): One billionth of a meter.
• Millimeters (mm): One thousandth of a meter.