Biological Evolution- is the refers to the cumulative changes that occurs ina population over a time.
The Cell Wall☺Hope this helps.
Answer:
Background
During the course of a bacterial infection, the rapid identification of the causative agent(s) is necessary for the determination of effective treatment options. We have developed a method based on a modified broad-range PCR and an oligonucleotide microarray for the simultaneous detection and identification of 12 bacterial pathogens at the species level. The broad-range PCR primer mixture was designed using conserved regions of the bacterial topoisomerase genes gyrB and parE. The primer design allowed the use of a novel DNA amplification method, which produced labeled, single-stranded DNA suitable for microarray hybridization. The probes on the microarray were designed from the alignments of species- or genus-specific variable regions of the gyrB and parE genes flanked by the primers. We included mecA-specific primers and probes in the same assay to indicate the presence of methicillin resistance in the bacterial species. The feasibility of this assay in routine diagnostic testing was evaluated using 146 blood culture positive and 40 blood culture negative samples.
Explanation:
Results
Comparison of our results with those of a conventional culture-based method revealed a sensitivity of 96% (initial sensitivity of 82%) and specificity of 98%. Furthermore, only one cross-reaction was observed upon investigating 102 culture isolates from 70 untargeted bacteria. The total assay time was only three hours, including the time required for the DNA extraction, PCR and microarray steps in sequence.
Answer:
Verdadero
Explanation:
Sabemos que los caracteres dependen de los genes. Y los genes pueden presentarse en forma de alelos dominantes, o alelos recesivos. La expresión de los alelos recesivos son enmascarados o escondidos por el alelo dominante. Es decir, que si ambos alelos se encuentran juntos en un heterocigota, solo el alelo dominante se expresará.
Entonces el alelo dominante expresa la característica que resulta dominante, mientras que el alelo recesivo expresa la característica recesiva.
Genotipo:
- Homocigota dominante ----> Expresa caracter dominante (Solo el alelo dominante esta presente)
- Heterocigota -------------------> Expresa el caracter dominante (Ambos alelos estan presentes, pero el dominante es quien se expresa)
- Homocigota recesivo --------> Expresa el caracter recesivo (solo alelos recesivos estan presentes)
Por ejemplo, si tenemos dos fenotipos rojo y amarillo, y sabemos que el color esta codificado por un gen dialelico llamado M. También supongamos que no sabemos qué alelo expresa qué color. Teniendo solo estos datos, no podemos decir si el rojo es el color dominante o si el amarillo lo es.
Sin embargo, si tenemos los siguientes genotipos acompañando esta información:
- MM--> Amarillo
- Mm--> Amarillo
- mm --> Rojo
Recién ahora podemos deducir que el caracter dominante es el amarillo.
