Number 4……………………………..
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If the new gene "works", then it will synthesize a missing enzyme or structural protein. A gene is a protein-coding nucleotide (DNA) sequence.
A gene is a fragment of DNA that is used by the cell to create a complementary mRNA sequence by a process called transcription.
Subsequently, this mRNA is then used to synthesize a protein by a process called translation.
When a gene is defective, a change in the nucleotide sequence (i.e., a mutation) can restore normal gene function and thus produce a functional protein.
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