Aeukaryotic gene was inserted into the dna of a bacterium. the bacterium then transcribed this gene into mrna and translated the mrna into protein. the protein produced was useless; it contained many more amino acids than the protein made by the eukaryote. why?

Eukaryotic genes are more complicated than bacterial genes because many of them have introns - these are stretches of DNA that need to be spliced out of the mRNA prior to translation. If you clone the original DNA gene sequence into a bacterium, it doesn't have splicing machinery - so you end up with many more amino acids than the protein made by the eukaryote (and likely a nonsense protein at that!).

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