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A biologist inserts a gene from a human liver cell into the chromosome of a...

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jazzhands253 | Student, Grade 9 | eNotes Newbie

Posted February 29, 2012 at 12:26 AM via web

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A biologist inserts a gene from a human liver cell into the chromosome of a bacterium......

The bacterium then transcribes and translates this gene. The protein  produced is useless  and is found to contain many more amino acids than does the protein made by the eukaryotic cell. Explain why.

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jazzhands253 | Student, Grade 9 | eNotes Newbie

Posted February 29, 2012 at 2:20 AM (Answer #1)

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I also need an outline for this please.

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apushstudent | Student, Grade 10 | eNoter

Posted April 28, 2012 at 6:43 PM (Answer #2)

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Once the gene is inside the prokaryotic bacterium it may be translated by the bacteria's ribosomes and make a type of RNA called preRNA.  preRNA undergoes a process calledRNA processing in which codons do not code for the gene (introns) are spliced from the expressable preRNA (Exons forExpressed).  Splicing is conducted by a protein-RNA complex called a spliceosome.  Spliceosomes are made up of 2 parts, snRNP's and protein.  snRNP's are the things that make splicing work.  snRPN's are made of snRNA and protein.  These snRPN's (small nuclear ribonucleoproteins) bind to the ends of the introns of preRNA and then cut the intron out and splice the two exons together.  This process of splicing differs between prokaryotes and eukaryotes.  The difference is calle d alternative RNA splicing.  This means that basically a prokaryote might have a different way of categorizing what is an intron and what is an exon.  The spliceosomes will cut the preRNA in different points and the number of nucleotides in the preRNA is reduced.  Once RNA processing is completed the RNA is now classified as mRNA (messenger RNA).  Now it can be tranlated to form a protein by the cooperative action of ribozomes and tRNA (transfer RNA).  Since the prokaryotic and eukaryotic versions of the gene differ in the number of nucleotides the number of amino acids used to produce the protein is different.

Source: Campbell Biology Seventh Edition AP Edition

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