Microbiology Glossary
Browse our comprehensive collection of 777 microbiology terms and definitions.
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Norovirus GI
Norovirus GI refers to genogroup I noroviruses, a group of non-enveloped positive-sense RNA viruses in the genus Norovirus family Caliciviridae that cause...
Norovirus GII
Norovirus GII refers to genogroup II noroviruses, a highly diverse group of non-enveloped positive-sense RNA viruses within the genus Norovirus family...
Norovirus GIV
Norovirus GIV refers to genogroup IV noroviruses, a small group of positive-sense RNA viruses in the genus Norovirus family Caliciviridae that infect humans...
Northern Blot
Northern blot is a laboratory method that separates RNA molecules by size through gel electrophoresis, transfers them onto a membrane, and uses labelled probes...
Nosocomial
Nosocomial infections are infections that arise during hospitalization or soon after discharge, and were neither present nor incubating at the time of...
Nucleoid
The nucleoid is an irregularly shaped region within a bacterial or archaeal cell that contains the primary chromosome and associated proteins, serving as the...
Nutrient Agar
Nutrient agar is a general-purpose solid medium containing peptone, beef or yeast extract, sodium chloride and agar, used to cultivate a wide range of...
Nutrient Broth
Nutrient broth is a liquid culture medium containing peptone, beef or yeast extract and sodium chloride, formulated to support the growth of a wide variety of...
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O'nyong-nyong Virus
O'nyong-nyong virus is an arthropod-borne virus in the genus Alphavirus of the family Togaviridae. It is transmitted by Anopheles mosquitoes and causes an...
Obligate Aerobe
An obligate aerobe is an organism that requires oxygen for aerobic respiration and cannot survive long without it. Explanation In obligate aerobes, oxygen...
Obligate Anaerobe
An obligate anaerobe is a microbe that cannot tolerate oxygen and must live in environments devoid of it. Explanation In obligate anaerobes, oxygen acts as a...
Obligate Intracellular Parasite
An obligate intracellular parasite is an organism that can only reproduce inside the living cells of its host, relying on host machinery for survival....
Obligate Parasite
An obligate parasite is an organism that must live in or on a host organism to complete its life cycle; without a suitable host it cannot survive or reproduce....
Omsk Hemorrhagic Fever Virus
Omsk hemorrhagic fever virus OHFV is an enveloped, single‑stranded RNA virus in the genus Flavivirus and the agent of Omsk hemorrhagic fever, a tick‑borne...
Onchocerca volvulus
Onchocerca volvulus is a parasitic nematode that infects humans and causes the disease onchocerciasis, also known as river blindness. Explanation Onchocerca...
Oncogenic Virus
An oncogenic virus is a virus that can contribute to the development of cancer in its host by disrupting normal control of cell growth and division....
Oncovirus
An oncovirus is a virus that can induce malignant transformation of infected cells, leading to tumour formation. Explanation Oncoviruses contribute to cancer...
Oocyst
An oocyst is a thick‑walled, resistant structure formed by certain parasitic protozoa after sexual reproduction, enclosing the zygote and eventually producing...
Open Reading Frame (ORF)
An open reading frame is a series of codons in DNA or RNA that has the potential to code for a protein. It begins with an initiation codon and is not...
Open Reading Frame (ORF)
An open reading frame ORF is a contiguous sequence of nucleotides in DNA or RNA that could potentially encode a polypeptide. It begins with a start codon and...
Open Reading Frame (ORF)
An open reading frame ORF is a continuous stretch of nucleotide sequence that starts with a start codon and continues without interruption until a stop codon....
Operator
An operator is a segment of DNA in a prokaryotic operon that interacts with regulatory proteins to control transcription of adjacent structural genes....
Operon
An operon is a functional unit in bacteria that comprises one or more structural genes and their regulatory sequences, transcribed together as a single mRNA...
Opportunistic Infection
An opportunistic infection is an infection caused by microorganisms that ordinarily do not produce disease in a healthy host but exploit weakened immune...