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Post transcription, introns are removed and exons are rearranged randomly. If that's the case (which it is according to the book EDEXCEL SNAB A2 topic 6) then shouldn't the protein produced be different every time? Shouldn't the order of amino acids be different? And if it is, doesn't that mean that the protein produced is different?
To quote : "When mRNA is produced, its introns are removed by spliceosomes and a different number of exons is put together at different orders which changes the sequence of amino acids in proteins."
Quote from the book:
- Genes contain sections that don't code for amino acids.
- These sections of DNA are called introns. All the bits that do code for amino acids are called exons.
- During transcription both introns and exons are copied into mRNA.
- The introns are then removed by a process called splicing -- introns are removed and exons joined forming mRNA strands. This takes place in the nucleus.
- The exons can be joined together in different orders to form different mRNA strands.
If this process happens,how can a gene code for a specific protein? This process means that exons are arranged differently, and this means that amino acids are arranged differently, and doesn't that mean that different proteins are going to be produced than the one coded for?