microorganism

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microorganism

 [mi″kro-or´gah-nizm]
a microscopic organism; those of medical interest include bacteria, fungi, and protozoa. Viruses are often classified as microorganisms, although they are sometimes excluded because they are not cellular and they are unable to replicate without a host cell.

mi·cro·or·gan·ism

(mī'krō-ōr'gan-izm),
A microscopic organism (plant or animal).

microorganism

/mi·cro·or·gan·ism/ (-or´gah-nizm) a microscopic organism; those of medical interest include bacteria, fungi, and protozoa. Viruses are often included, but are sometimes excluded because they are not cellular and are unable to replicate without a host cell.

microorganism

[-ôr′gəniz′əm]
Etymology: Gk, mikros + organon, instrument
any tiny, usually microscopic entity capable of carrying on living processes. It may be pathogenic. Kinds of microorganisms include bacteria, fungi, protozoan, and viruses.

microorganism

An organism detected by microscopy—e.g., viruses, bacteria, fungi and intracellular parasites (protozoans).

microorganism

 A organism detected by microscopy–eg, viruses, bacteria, fungi and intracellular parasites–protozoans; bug

mi·cro·or·gan·ism

(mī'krō-ōr'găn-izm)
A microscopic organism (plant or animal).

microorganism

or

microbe

any microscopic organism such as a BACTERIUM, FUNGUS, PROTOZOAN, microscopicALGA or member of the ARCHAEA.

Microorganism

An organism (life form) that is too small to be seen with the naked eye.

microorganism

; MO generic term denoting bacteria, fungi, rickettsiae and viruses

mi·cro·or·gan·ism

(mī'krō-ōr'găn-izm)
A microscopic organism (plant or animal).

microorganism

(mī´krō ōr´gənizəm),
n a microscopic living organism, such as a bacterium, virus, rickettsia, yeast, or fungus. These may exist as part of the normal flora of the oral cavity without producing disease. With disturbance of the more or less balanced interrelationship among the organisms or between the organisms and host resistance, individual forms may overgrow and induce disease in the host's tissues. Those foreign to the individual may invade and produce pathologic processes.

microorganism

a microscopic organism; those of veterinary interest include bacteria, rickettsiae, viruses, fungi and protozoa.
References in periodicals archive ?
Although studies of unicellular organisms point to the cellular nature of the system generating circadian rhythms, the circadian pacemaker in higher organisms is located in cells of specific structures of the organism.
We don't know what it does in unicellular organisms, but we can now place the origin of genes that are associated with multicellularity in unicellular organisms.
Another theory is that the fossils are protists, which are unicellular organisms lacking a definite cellular arrangement.
The first is the claim that "the fossil [record] shows unicellular organisms such as cyanobacteria around three and one-half billion years ago and then suddenly the Cambrian explosion 530 million years ago, with nothing much appearing in-between.
Scientists suspect that many microbial species responsible for human illnesses first preyed upon amoebas, unicellular organisms found in aquatic environments.
During earth's history, complex multicellular life has evolved from unicellular organisms along five independent paths, which are: animals, plants, fungi, red algae and brown algae.
In nature, Meganucleases come from unicellular organisms, bacteria, yeasts, algae and some plant organelles.
The xenophyophores, however, actually are unusually large, unicellular organisms, and the residents of the Darwin Mounds rank as giants among giants, single-cell organisms that can reach 20 centimeters in diameter.
Free-living, unicellular organisms called choanoflagellates, however, could be on every person's family tree, so long as it was a gigantic one.
Adolf Seilacher of Tubingen University in Germany proposed in 1983 that the fossils represent massive unicellular organisms whose bodies were fluid-filled compartments arranged like the cells of an air mattress (SN: 7/8/95, p.
In unicellular organisms, protein-based circuits act in place of a nervous system to control behavior," Bray states.