Question

Polyribosomes are formed when ribosomes are attached by

• A. tRNA
• B. rRNA
• C. mRNA
• D. All of the above

Answer 1

Answer: (C)

mRNA

Ribosomal RNAs (rRNAs) are structural and functional part of ribosomes which serve as site for proteins synthesis. Transfer RNAs (tRNAs) decipher the mRNA information and transfer the appropriate amino acid to a growing polypeptide chain during protein synthesis. Messenger RNAs (mRNAs) carries the information for amino acid sequence of one or more polypeptides specified by a gene or set of genes. Translation starts with binding of mRNA to initiation complex that has ribosome and initiation factors. When mRNA is bound to more than one ribosome, the structure is called polysome or polyribosome which facilitates simultaneous production of multiple copies of same polypeptide. Correct answer is option C.