Final answer:
RNA processing involves removing introns, adding a 5' cap and a poly-A tail, and occurs in the nucleus of eukaryotic cells to produce mature mRNA, which is not necessary for prokaryotic cells.
Step-by-step explanation:
The correct statements regarding RNA processing are that it occurs in the nucleus, involves the removal of introns, and results in the formation of a mature mRNA molecule. RNA processing is a crucial step in eukaryotic cells to produce a translatable mRNA from a pre-mRNA transcript. Notably, RNA processing is not necessary for prokaryotic cells, as their mRNA does not contain introns, and transcription and translation occur almost simultaneously without the need for a nucleus.
In eukaryotic cells, RNA processing includes adding a 5' cap, a poly-A tail, and splicing where introns are excised and exons are joined to form a mature mRNA that can exit the nucleus for translation in the cytoplasm. Thus, RNA transcription takes place before protein translation, with necessary modifications occurring within the nucleus.