Axénico: Diferenzas entre revisións

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Miguelferig (conversa | contribucións)
creado en parte a partir de en:Axenic.
 
Miguelferig (conversa | contribucións)
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==Preparación==
Os cultivos axénicos de [[microorganismo]]s prepáranse normalmente realizando unha [[dilución en serie]] dun cultivo mixto xa existente. Este cultivo dilúese sucesivamente ata o punto no que as mostras que se extraian del conteñan só unhas poucas células do microorganismo, idealmente só unha (no caso das especies con [[reprodución asexual]]). Estes subcultivos fanse crecer ata que se poida comprobar a identidade dos organismos que o constitúen. A selección dos cultivos que conteñan só o organismo procurado producirá un cultivo axénico.
Axenic cultures of [[microorganism]]s are typically prepared using a [[serial dilution|dilution series]] of an existing mixed culture. This culture is successively diluted to the point where subsamples of it contain only a few individual organisms, ideally only a single individual (in the case of an [[asexual reproduction|asexual]] [[species]]). These subcultures are allowed to grow until the identity of their constituent organisms can be ascertained. Selection of those cultures consisting solely of the desired organism produces the axenic culture.
 
Axenic cultures are usually checked routinely to ensure that they remain axenic. One standard approach with microorganisms is to spread a sample of the culture onto an [[agar plate]], and to [[Incubator (microbiology)|incubate]] this for a fixed period of time. The agar should be an enriched medium that will support the growth of common "contaminating" organisms. Such "contaminating" organisms will grow on the plate during this period, identifying cultures that are no longer axenic.