Final answer:
To measure the expression of all genes in an organism simultaneously, a microarray is the appropriate assay. This method allows for comparison of thousands of genes' expression patterns, utilizing cDNA and fluorescent labeling to detect active genes.
Step-by-step explanation:
If you wish to measure the expression of all the genes in an organism at once, you should use a microarray. This method enables researchers to analyze the gene expression of thousands of genes by placing different DNA fragments on a chip or glass slide. The DNA or cDNA fragments are then hybridized with fluorescently labeled targets to identify which genes are active. A microarray analysis can be instrumental in comparing the gene-expression patterns between various samples, such as healthy versus cancerous cells, or in different conditions.
Microarrays apply nucleic acid hybridization and are sensitive enough to detect even single nucleotide differences between sequences. This technology provides insights into gene expression at the transcriptional level by using cDNA from mRNAs to determine the transcriptome of a particular tissue or condition. Additionally, microarrays can be used for genotyping and are especially powerful in research settings, despite the cost of the sophisticated detection equipment and analysis software required.
The assay that would be used to measure the expression of all the genes in an organism at once is a Microarray assay. Microarray analysis is a technique that allows the comparison of gene expression patterns between different cell types. It involves the immobilization of DNA or cDNA fragments on a chip and labeling them with different fluorescent dyes. This allows for the detection of gene expression levels and the identification of active genes and sequences.