Question

____(A)______ contains a single ______(B)________ and several ____(C)____ attached to it.

• A. A- Polysome, B - mRNA, C -ribosomes
• B. A - Polysome, B - ribosome, C -mRNAs
• C. A - Transcription unit, B - mRNA, C - enzymes
• D. A - Transcription unit, B - enzyme, C - mRNAs

Answer 1

The correct option is A

A- Polysome, B - mRNA, C -ribosomes

A polysome contains two or more ribosomes bound to a single mRNA molecule similar to beads on a string. The ribosomes in the polysome are involved in translating the mRNA into polypeptides. Due to the presence of several ribosomes many copies of the polypeptide can be formed from a single mRNA molecule almost simultaneously.

Transcription is the process by which information from one of the strands of DNA is copied to mRNA.
A transcription unit is a segment of DNA that takes part in the process of transcription. It consists of 3 regions - a promoter, structural gene and terminator.