The correct answer is: introns
Processing of mRNA is process that occurs only in eukaryotic cells. After the transcription, newly formed mRNA molecule is called and it must be processed into a messenger RNA (mRNA). Processing includes:
• Addition of a 5' cap to the beginning of the RNA
• Polyadenilation- addition of a poly-A tail (tail of A nucleotides) to the end of the RNA
• Splicing- removal of introns and linking the exons
After these steps mRNA is mature and used for the further steps (e.g. translation).
Sometimes some genes are alternatively spliced.
Answer:
I believe the correct answer is nucleus.
The presence of limestone<span> and other calcium carbonate rock in </span>lakes<span> and streams helps to maintain a constant pH </span>because<span> the minerals react with the excess </span>acid<span>. However, </span>acid rain<span> eventually can overcome the buffering capacity of the surface water.
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