NEET2008ZoologyMolecular Basis of InheritanceActual
Polysome is formed by
Options
- Aseveral ribosomes attached to a single mRNA
- Bmany ribosomes attached to a strand of endoplasmic reticulum
- Ca ribosome with several subunits
- Dribosomes attached to each other in a linear arrangement
Correct answer
A. several ribosomes attached to a single mRNA
Step-by-step solution
In prokaryotes, ribosomes attach to the 5^ end of mRNA as soon as transcription begins. A bunch of ribosome moves along a single mRNA molecule adding 15 amino acids/second to the polypeptide chain, almost the same speed at which RNA polymerase transcribes the mRNA. The group of ribosomes together with the single mRNA molecules, they are translating is called polysome. The use of polysomes is advantageous to a cell since, the overall rate of protein synthesis is increased compared to the rate that would occur if the