Microorganisms

What are the four main types of microorganisms?

The four main types of microorganisms are bacteria, fungi, protozoa, and viruses.

Give examples of bacteria and their characteristics.

• Bacteria: Single-celled organisms.
• Examples:
  • Lactobacillus (used in yogurt production)
  • E. coli (some strains are harmful, others are beneficial in the gut)
  • Salmonella (food poisoning)

Give examples of fungi and their characteristics.

• Fungi: Can be single-celled (yeast) or multicellular (molds, mushrooms).
• Examples:
  • Saccharomyces cerevisiae (yeast, used in bread making and brewing)
  • Penicillium (produces penicillin, a common antibiotic, and used in cheese ripening)
  • Aspergillus (common mold, some species can produce toxins)

Give examples of protozoa and their characteristics.

• Protozoa: Single-celled eukaryotic organisms, often motile.
• Examples:
  • Amoeba (known for changing shape)
  • Paramecium (ciliated protozoan)
  • Plasmodium (causes malaria)

Give examples of viruses and their characteristics.

• Viruses: Non-cellular entities consisting of genetic material (DNA or RNA) enclosed in a protein coat; require a host cell to replicate.
• Examples:
  • Influenza virus (causes flu)
  • SARS-CoV-2 (causes COVID-19)
  • Bacteriophages (viruses that infect bacteria)

When did Louis Pasteur discover the role of microorganisms in fermentation?

Louis Pasteur discovered the process of fermentation, specifically the role of microorganisms in it, around 1857.

Discovery of antibiotics

Alexander Fleming discovered antibiotics in 1929

Discovery of vaccine

Edward Jenner discovered the vaccine of smallpox in 1782

Pasteurisation

The process of heating milk fo 15 to 20 seconds and storing it in cool temperatures to disfavour the growth of microorganisms