Microbiology Basics Quiz

Microorganisms Overview

• Mosquitoes are not classified as microorganisms.
• Helminths are defined as parasitic worms.
• Viruses are categorized as noncellular microorganisms.

Immunology and Microbiology

• Immunologists study the immune response to infections caused by microorganisms.
• Industrial microbiologists do not manipulate bacterial strains to be less pathogenic.

Specialized Fields

• Geomicrobiology investigates the role of microbes in cave formation.
• Astrobiology studies the potential for microbial life beyond Earth.
• Decomposers recycle nutrients by breaking down dead matter and waste.

Energy and Nutrient Flow

• Majority of Earth's atmospheric oxygen results from microbial photosynthesis.
• The common ancestral cell gave rise to three cell types: eukaryotes, archaea, and bacteria, with the first cells appearing around 3.5 billion years ago.

Evolution and Biotechnology

• Evolution describes the gradual changes in living organisms over time.
• Genetic engineering involves humans manipulating microbial genes.
• A clear example of biotechnology is Escherichia coli producing human insulin.

Traditional Uses and Bioremediation

• Traditional human uses of microorganisms include baking bread.
• Bioremediation uses microbes to detoxify sites contaminated with heavy metals.

Pathogens and Infectious Diseases

• Pathogens are microorganisms that cause diseases.
• Respiratory diseases are the leading infectious diseases globally.
• The U.S. has fewer communicable disease-related deaths compared to other global regions.

Cellular Comparisons

• Bacteria and eukaryotes both possess a cell membrane.
• Archaea and eukaryotes share similar small subunit rRNA sequences.
• Viruses lack cell structure, setting them apart from other microorganisms.
• Viruses consist only of hereditary material wrapped in a protein coat.

Size and Scale of Cells

• Eukaryotic cells are generally ten times larger than bacterial or archaeal cells.
• Archaeal cells are similar in size to bacterial cells.
• Viruses are smaller than bacterial or archaeal cells but larger than macromolecules.

Historical Microbiology

• Louis Pasteur is incorrectly associated with demonstrating anthrax causation—his primary contributions were related to spontaneous generation.
• Pasteur used swan-necked flasks to allow air exposure while preventing bacteria from contaminating the broth.

Microbiological Standards

• Koch's postulates are used to identify specific microbes as causes of specific diseases.
• Recent discoveries significantly impact the understanding of microbiology.
• The microbiome encompasses all microbes within a particular environment.

Scientific Method and Taxonomy

• The scientific method excludes belief in preconceived ideas as a legitimate process.
• Experimentation is essential for obtaining objective data, while publication is not part of the method itself.
• Taxonomy focuses on the identification and classification of organisms without relying on common names.

Taxonomic Hierarchy

• Organisms are classified in a hierarchical structure, with classification defining the orderly arrangement into taxa.
• Kingdom is the highest taxon that encompasses all others.
• Species is the smallest and most significant taxon.
• Correct descending taxonomic order is Family, Genus, Species.