MICROBIO Lecture 1 REG FLASH

Key vocabulary terms from the introductory microbiology lecture, covering major organism groups, infectious agents, historical milestones, lab concepts, and ecological roles.

Microbe

A microscopic entity; may be living (microorganism) or non-living (acellular infectious agent).

Microorganism

A living microbe such as bacteria, protozoa, fungi, or microscopic helminth stages.

Acellular Infectious Agent

Biological material (e.g., viruses, viroids, prions) that lacks cellular structure and is not considered alive.

Immunology

Study of the body’s defenses against infection.

Epidemiology

Science that tracks disease occurrence, distribution, and control in populations.

Pathology

Branch of medicine that investigates disease causes and effects.

Prokaryote

Cell lacking a nucleus and membrane-bound organelles; includes bacteria and archaea.

Bacteria

Diverse, ubiquitous prokaryotes; major focus of clinical microbiology because many are pathogenic.

Archaea

Prokaryotes distinct from bacteria; no known human pathogens.

Eukaryote

Cell with a true nucleus and membrane-bound organelles.

Protist

Eukaryotic kingdom that includes protozoa and algae.

Protozoan

Single-celled, usually motile protist; many species are human pathogens (e.g., Plasmodium).

Fungus (Fungi)

Eukaryotes with chitinous cell walls; act as decomposers and occasional pathogens.

Helminth

Parasitic worm; microscopic only in larval stages (e.g., tapeworms, roundworms).

Arthropod Vector

Insect or arachnid that transmits pathogens (e.g., mosquitoes, ticks, fleas).

Virus

Obligate intracellular parasite composed of nucleic acid within a protein coat (capsid).

Capsid

Protein shell that encloses viral genetic material.

Obligate Intracellular Parasite

Agent that can replicate only inside a host cell (e.g., viruses).

Viroid

Infectious, naked RNA molecule; known to infect plants only.

Prion

Infectious misfolded protein that induces abnormal folding in host proteins (e.g., Creutzfeldt-Jakob).

Motility

Ability of an organism to move independently (flagella, cilia, pseudopods).

Cell Wall

Rigid layer outside some cells; absent in protozoa, present in bacteria and fungi.

Algal Bloom

Rapid overgrowth of algae due to excess nutrients/CO₂; can create toxic ‘red tides.’

Red Tide

Marine algal bloom producing red pigments and toxins hazardous to humans and wildlife.

Decomposition

Breakdown of organic matter, largely performed by fungi and bacteria.

Microbiome

Total community of microbes living on and in the human body.

Germ Theory of Disease

Concept that specific microorganisms cause specific diseases.

Koch’s Postulates

Experimental criteria to link a microbe with a disease cause.

Pasteurization

Controlled heating process that reduces microbial load without boiling (developed by Louis Pasteur).

Tyndallization

Intermittent boiling/ cooling cycles that destroy heat-resistant microbes; ‘super-pasteurization.’

Biogenesis

Principle that living cells arise only from pre-existing cells.

Abiogenesis (Spontaneous Generation)

Discredited idea that life arises spontaneously from non-living matter.

Cell Theory

Framework stating that all organisms are made of cells, cells arise from cells, and are the basic unit of life.

DNA

Universal hereditary molecule storing genetic information in all living cells.

Glycolysis

Universal metabolic pathway that breaks down glucose to pyruvate, yielding energy.

Recombinant DNA

Technology that joins DNA from different sources, enabling production of proteins like human insulin in microbes.

Bioremediation

Use of microbes to clean environmental pollutants (e.g., oil-eating Pseudomonas).

Lysozyme

Antibacterial enzyme found in saliva and tears; discovered by Alexander Fleming.

Penicillin

First widely used antibiotic, produced by Penicillium fungi; discovered by Alexander Fleming.

Antibiotic

Substance produced by microbes (or synthetically) that inhibits or kills other microorganisms.

Statins

Cholesterol-lowering drugs originally derived from fungal metabolites.

Cyclines (e.g., Cyclosporine)

Fungal-derived immunosuppressant drugs used in transplantation and autoimmunity.

Carbon Recycling

Conversion of CO₂ to organic carbon and back, heavily mediated by photosynthetic algae and microbes.

Obligate Anaerobe

Organism that cannot survive in the presence of oxygen (contrast to aerobic microbes).

Swan-Neck Flask

Curved-neck vessel used by Pasteur to disprove spontaneous generation by preventing airborne contamination.

Selective Vector Control

Disease prevention strategy targeting arthropods that transmit pathogens (e.g., mosquito abatement).