Explain the roles of mRNA and tRNA in protein
synthesis.
DONE

Messenger RNA (mRNA) molecules carry the coding sequences for protein synthesis and are called transcripts; ribosomal RNA (rRNA) molecules form the core of a cell's ribosomes (the structures in which protein synthesis takes place); and transfer RNA (tRNA) molecules carry amino acids to the ribosomes during protein.

Explanation:

the second type of galaxy is called a barred spiral, which has a thing called a bar straddling the nucleus

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