A polysome is . a. the complex that adds a poly(A) tail onto an mRNA b. an mRNA transcript to which multiple ribosomes are attached c. the combination of a large and a small ribosomal subunit d. the promoter assembly at the site of transcription initiation e. the complex where mRNA splicing occurs

b. an mRNA transcript to which multiple ribosomes are attached

Explanation: polysome consist of mRNA complex and two or more ribosome coming together to translate mRNA into a polypetide or amino acid. It helps produce many polypeptide from a single mRNA.

Different ribosomes bind to the mRNA at different time elongating the polypeptide chain. We have the free( non-poly A ) and memberane bound (poly A) polysome.

all matter is made up of atoms

in any element all atoms are the same

elements in a compound are always in a constant ratio: apex