Microbiology Quiz: Bacteria, Archaea, and Fungi

Introduction to Microbiology

• Microbes are microscopic organisms, including bacteria, archaea, fungi, protists, and viruses.
• Viruses are acellular and their classification as "living" is debated.
• Understanding microbes is crucial for addressing emerging infectious diseases, improving food safety, developing new medicines, and advancing biotechnology.
• Microbial sizes are significant for techniques like filtration (0.2 µm filters).
• Units of measurement include millimeters (mm), micrometers (µm), nanometers (nm), and angstroms (Å).
• Cell theory states all living things are composed of cells, and microbes are part of this.
• Spontaneous generation (life from non-living matter) is disproven by experiments
• Microbes often exist in communities (e.g., biofilms) with complex interactions.
• Horizontal gene transfer means bacteria exchange genetic material without reproduction.
• Microbial diversity is broader than plant or animal diversity, reflected by metabolic capabilities, habitats, and evolutionary history.

Microbial Classification

• Six major microbial groups: Viruses, Bacteria, Archaea, Fungi, Protozoa, Algae.
• Bacteria are prokaryotic with peptidoglycan cell walls, use various energy sources, and some are beneficial, while others are pathogenic.
• Archaea are prokaryotic with no peptidoglycan, thrive in extreme environments, and generally aren't pathogenic.
• Fungi are eukaryotic with chitin cell walls, obtain energy from organic chemicals, and can be unicellular or multicellular.
• Protozoa are eukaryotic, motile organisms, and often absorb or ingest organic chemicals; some are beneficial, some are pathogenic.
• Algae are eukaryotic organisms with cellulose cell walls, and use photosynthesis.

Germ Theory of Disease and Koch's Postulates

• The Germ Theory of Disease proposes that microorganisms cause infectious diseases.
• Koch's Postulates are criteria to link a specific microbe to a specific disease.
  • The microbe is present in all diseased cases, absent from healthy ones.
  • The microbe can be isolated and grown in pure culture.
  • Introducing the cultured microbe to a healthy host results in disease.
  • The same microbe can be isolated from the newly diseased host.

Pasteur, Lister, Semmelweis, and Nightingale

• Pasteur disproved spontaneous generation and developed pasteurization.
• Lister promoted antiseptic surgery to reduce infections.
• Semmelweis advocated for handwashing to prevent puerperal fever.
• Nightingale implemented sanitation programs to reduce disease transmission.

Chemotherapy and Antibiotics

• Chemotherapy uses chemical substances to treat diseases.
• Antibiotics are substances produced by microbes to kill or inhibit other microbes.

Microbiology and Genetics

• Microbial genetics studies how microbes inherit traits.
• Molecular biology examines DNA sequencing and gene expression.
• Genomics studies an organism's complete set of genes.
• Recombinant DNA Technology creates new genetic combinations using DNA.
• Gene therapy uses recombinant DNA to replace or repair defective genes.
• Genetic Engineering modifies genetic material to create desirable traits.
• PCR amplifies specific DNA sequences.
• DNA sequencing determines nucleotide order in DNA.

Microbiology and the Environment

• Microbial ecology studies interactions between microbes and their environments.
• Microbes play essential roles in nutrient cycling (carbon, nitrogen, sulfur, phosphorus).

Emerging Infectious Diseases

• Emerging Infectious Diseases (EIDs) are new or increasing infectious diseases.
• Factors that contribute to EIDs include globalization, climate change, antibiotic resistance.

Test your knowledge on the characteristics of microorganisms, including bacteria, archaea, fungi, and viruses. This quiz covers their unique features, roles in ecosystems, limitations of Koch's postulates, and more. Suitable for students studying microbiology or related life sciences.