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Biology LibreTexts

1: Fundamentals of Microbiology

  • Page ID
    2695
  • Microbiology is the study of microscopic organisms, those being unicellular (single cell), multicellular (cell colony), or acellular (lacking cells). As an application of microbiology, medical microbiology is often introduced with medical principles of immunology as microbiology and immunology. Otherwise, microbiology, virology, and immunology as basic sciences have greatly exceeded the medical variants, applied sciences.

    • 1.1: Introduction to Microbiology
      Microorganisms are typically too small to be seen with the naked eye. Bacteria, fungi, viruses, protozoa, and algae are the major groups of microorganisms. The vast majority of microorganisms are not harmful but rather beneficial. Microbiota refers to all of the microorganisms that live in a particular environment. A microbiome is the entire collection of genes found in all of the microbes associated with a particular host.
    • 1.2: Cellular Organization - Prokaryotic and Eukaryotic Cells
      here are two basic types of cells in nature: prokaryotic and eukaryotic. Prokaryotic cells are structurally simpler than eukaryotic cells. The smaller a cell, the greater its surface to volume ratio. The smaller the surface to volume ratio, the more structurally complex (compartmentalized) a cell needs to be in order to carry out life functions. There are fundamental differences between prokaryotic and eukaryotic cells.
    • 1.3: Classification - The Three Domain System
      Phylogeny refers to the evolutionary relationships between organisms. Organisms can be classified into one of three domains based on differences in the sequences of nucleotides in the cell's ribosomal RNAs (rRNA), the cell's membrane lipid structure, and its sensitivity to antibiotics. The three domains are the Archaea, the Bacteria, and the Eukarya. Prokaryotic organisms belong either to the domain Archaea or the domain Bacteria; organisms with eukaryotic cells belong to the domain Eukarya.
    • 1.E: Fundamentals of Microbiology (Exercises)
      These are homework exercises to accompany Kaiser's "Microbiology" TextMap. Microbiology is the study of microorganisms, which are defined as any microscopic organism that comprises either a single cell (unicellular), cell clusters or no cell at all (acellular). This includes eukaryotes, such as fungi and protists, and prokaryotes. Viruses and prions, though not strictly classed as living organisms, are also studied.

    Thumbnail: A cluster of Escherichia coli bacteria magnified 10,000 times. Image used with permission (Public Domain; Eric Erbe, digital colorization by Christopher Pooley, both of USDA, ARS, EMU).

    Contributors

    • Dr. Gary Kaiser (COMMUNITY COLLEGE OF BALTIMORE COUNTY, CATONSVILLE CAMPUS)