Strain meaning in biology

\( \newcommand\) • • • • • • • • • • • • • Characteristics of Bacterial Growth Even on general purpose growth media, bacteria can exhibit characteristic growth patterns. On agar plates, bacteria grow in collections of cells called colonies. Each colony arises from a single bacterium or a few bacteria. Although individual cells are too small to be viewed, masses of cells can be observed. Colonies can have different forms, margins, elevations, and colors. Observing colony characteristics is one piece of information that microbiologists can use to identify unknown bacteria. Shown below are isolated colonies of S. aureuson a blood agar plate. Colonies that are visible to the human naked eye contains tens of thousands or even millions of individual bacteria!! Image 1:Notice individually isolated colonies:Large, creamy white, circular,beta-hemolytic colonies typical o fStaphylococcus aureuscultured on Blood agar. Image by Rebecca Buxton, University of Utah, Salt Lake City, UT. Colony morphologycan be an aid in the identification of microorganisms. Although colony morphology cannot be employed as the sole identifying criterion, it is a useful trait in the classification of many common types of microorganisms. Six parameters are normally used to describe microbial colonies growing on an agar surface: a. Size:pinpoint, small, medium, or large; range:

A prototype virus may or may not be the first isolated virus of a group. It's essentially the same as a "reference" virus -- in fact, the In many cases the reference virus is the first isolate, but it isn't necessarily the case. The ICTV is the official body that determines reference strains, and they may choose a different virus as the reference/prototype. For example the first isolate may turn out to be unusual or an outlier in same way, so that a more typical strain may be chosen as a reference or prototype (I don't know offhand of examples of this though). "Prototype" is often used in a broader sense as well, where a group of viruses can act as prototypes for a still broader group. For example, virus strain: Different lines or isolates of the same virus (e.g., from different geographical location or patients) prototype: the first example of something, such as a machine or other industrial product, from which all later forms are developed I think prototype of virus strain is first isolated virus of that strain. Refferences Principles of Molecular Virology fourth edition; Alan J. Cann; page 64.

Synonyms of strain • noun • as in lineage • as in melody • as in shred • as in type • as in stress • verb • as in to pull • as in to filter • as in to struggle • as in to drip • as in to stretch • as in to tighten • as in to hug • • as in lineage • as in melody • as in shred • as in type • as in stress • as in to pull • as in to filter • as in to struggle • as in to drip • as in to stretch • as in to tighten • as in to hug • Entries Near •

1. A population of homogeneous organisms possessing a set of defined characteristics; in bacteriology, the set of descendants that retains the characteristics of the ancestor; members of a strain that subsequently differ from the original isolate are regarded as belonging either to a substrain of the original strain, or to a new strain The American Heritage® Medical Dictionary Copyright © 2007, 2004 by Houghton Mifflin Company. Published by Houghton Mifflin Company. All rights reserved. strain noun AIDS An HIV isolate from a person or group of persons given its own unique identifier, or strain name–eg, MN, LAI Orthopedics An overuse injury verb To injure by overuse; to wear out or stress beyond normal limits; straining may be associated with tissue microtearing Ophthalmology Overuse of eyes, resulting in transient discomfort Vox populi verbTo filter; remove particles from a fluid 1. A population of homogeneous organisms possessing a set of defined characters. bacteriology The set of descendants that retains the characteristics of the ancestor; members of a strain that subsequently differ from the original isolate are regarded as belonging either to a substrain of the original strain, or to a new strain. A. Your doctor is more concerned about your health. So accept his advice and improve in your health. There is virtually no medical condition that will keep you from doing any type of exercise. Even people with heart failure -- who were long told not to exercise at all -- ca...

When some disease-causing viruses enter host cells, they start making new copies of themselves very quickly, often outpacing the immune system’s production of protective antibodies. Rapid virus production can result in cell death and spread of the virus to nearby cells. Some viruses replicate themselves byintegratinginto the host cell genome, which can lead to chronic illness or malignant transformation and cancer. virus, infectious agent of small size and simple The earliest indications of the biological nature of viruses came from studies in 1892 by the Russian scientist contagium vivum fluidum, meaning that it was a live, reproducing organism that differed from other organisms. Both of these investigators found that a The unique nature of these agents meant that new methods and Wilson Smith, Christopher H. Andrewes, and Patrick P. Laidlaw were able to transmit A significant advance was made by the American scientists Viruses, Bacteria, and Diseases Scientists were soon able to detect the number of bacterial viruses in a culture vessel by measuring their ability to break apart (lyse) adjoining bacteria in an area of bacteria (lawn) overlaid with an inert gelatinous substance called Advancements that have been made in chemistry, physics, and Discover how a benign bacterial virus can be employed to enhance the performance of lithium-oxygen storage batteries The revolution that took place in the field of This article discusses the fundamental nature of viruses: what they ar...

Learning Objectives • Explain the mechanism of genetic complementation Complementation refers to a relationship between two different strains of an organism which both have homozygous recessive mutations that produce the same phenotype (for example, a change in wing structure in flies) but which do not reside on the same (homologous) gene. These strains are true breeding for their mutation. If, when these strains are crossed with each other, some offspring show recovery of the wild-type phenotype, they are said to show “genetic complementation”. When this occurs, each strain’s haploid supplies a wild-type allele to “complement” the mutated allele of the other strain’s haploid, causing the offspring to have heterozygous mutations in all related genes. Since the mutations are recessive, the offspring will display the wild-type phenotype. A complementation test (sometimes called a “cis-trans” test) refers to this experiment, developed by American geneticist Edward B. Lewis. It answers the question: “Does a wild-type copy of gene X rescue the function of the mutant allele that is believed to define gene X?”. If there is an allele with an observable phenotype whose function can be provided by a wild type genotype (i.e., the allele is recessive), one can ask whether the function that was lost because of the recessive allele can be provided by another mutant genotype. If not, the two alleles must be defective in the same gene. The beauty of this test is that the trait can serve a...