Microbiology Glossary
Browse our comprehensive collection of 777 microbiology terms and definitions.
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Prokaryote
Prokaryotes are unicellular organisms whose genetic material is not enclosed by a membrane. Instead of a true nucleus, their DNA resides in a nucleoid, and...
Propagated Epidemic
A propagated epidemic is an outbreak in which an infectious agent spreads through person‑to‑person transmission, producing successive waves of cases. Unlike a...
Protective Antigen
Protective antigen is an 83‑kilodalton protein produced by Bacillus anthracis as one of the three components of the anthrax toxin. It binds to host cell...
Protozoa
Protozoa are single‑celled eukaryotic organisms that lack a rigid cell wall and feed on organic matter. They are typically motile and are distinguished by...
Pseudohyphae
Pseudohyphae are chains of elongated budding yeast cells that remain attached after cell division. Unlike true hyphae, they exhibit constrictions at the septal...
Pseudomonas aeruginosa
Pseudomonas aeruginosa is a Gram‑negative, rod‑shaped bacterium with a single polar flagellum. It belongs to the Gammaproteobacteria and is non‑fermentative,...
Psychrophiles
Psychrophiles are organisms whose optimal growth temperature is 15 °C or lower and that cannot thrive at moderate or high temperatures. Many are capable of...
Pure Culture
A pure culture is a population of microorganisms consisting of a single species or strain with no contaminating organisms. It is derived from a mixed...
Puumala Virus
Puumala virus is a member of the genus Orthohantavirus family Hantaviridae and causes a milder form of haemorrhagic fever with renal syndrome known as...
Q
qPCR (quantitative PCR)
qPCR, or quantitative polymerase chain reaction, is a technique that amplifies specific nucleic acid sequences while measuring the amount of product formed in...
Qualitative Test
A qualitative test identifies the presence, identity or characteristics of a substance or organism without measuring its quantity. It yields descriptive or...
Quantitative Test
A quantitative test determines the amount, concentration or numerical value of a substance, organism or activity in a sample rather than simply detecting its...
Quarantine
Quarantine is the practice of separating and restricting the movement of individuals or animals who may have been exposed to a contagious disease but are not...
Quorum Sensing
Quorum sensing is a cell‑density‑dependent communication process used by bacteria and some archaea to coordinate collective behaviour through the production...
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Rabies Lyssavirus
Rabies lyssavirus RABV, formerly called rabies virus, is the type species of the genus Lyssavirus family Rhabdoviridae. It is a non‑segmented, negative‑sense...
Rabies virus
The rabies virus is an enveloped, bullet‑shaped RNA virus of the genus Lyssavirus that causes fatal encephalitis in mammals, including humans. Explanation The...
Ravn Virus
Ravn virus is one of two viruses classified in the species Marburg marburgvirus within the genus Marburgvirus family Filoviridae. It is a negative‑sense,...
Recombinant DNA
Recombinant DNA refers to DNA molecules created by joining genetic material from different sources to form sequences that do not occur naturally, enabling the...
Replication
Replication is the process by which genetic material is copied to produce identical molecules, ensuring faithful transmission of information during cell...
Reservoir
A reservoir is any organism, population or environment in which a pathogen normally lives and multiplies, serving as a long‑term source of infection for other...
Resistance
Resistance in microbiology refers to the ability of microorganisms to survive and proliferate despite exposure to agents or conditions that would normally...
Respiration
Respiration in biology is the energy‑generating process in which cells oxidize substrates and transfer electrons through membrane‑bound carriers to a terminal...
Respiratory Syncytial Virus (RSV)
Respiratory syncytial virus RSV is an enveloped, non segmented, negative‑sense RNA virus in the genus Orthopneumovirus family Pneumoviridae that causes lower...
Reston Ebolavirus
Reston ebolavirus is a species of the genus Ebolavirus first recognized during an outbreak among cynomolgus macaques at a primate quarantine facility in...