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Old 04-18-2010
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Question More protiens than there are genes?

The molecular basis behind the presence of far more proteins than there are respective genes is explained by which of the following in humans --- bacteria respectively?

A- mRNA both side reading --- Polycistronic mRNA
B- DNA template and coding strands transcription --- Alternative splicing
C- Alternative splicing --- Polycistronic mRNA
D- Redundancy --- Degenerate code
E- Gene variation --- Posttranslational modification
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Old 04-18-2010
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the ans is C. human eukaryotic mRNA undergo alternative splicing which allows diff proteins to be expressed by the same gene eg:diff dopamine receptors (so all eukaryotes mRNA are monocistronic). in contrast prokaryotics are both monocistronic and polycistronic.
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Old 04-19-2010
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yes the answer is C. i agree with dr. achistikbenny.
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Old 11-29-2015
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option C

alternative splicing in humans can create several proteins from a single gene.

polycistronic mRNA in bacteria: 1 gene-->1 mRNA--> several proteins coded

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