Outline an experimental approach to determining the average chain growth rate for transcription in vivo. Chain growth rate is the number of nucleotides polymerized per minute per RNA chain. Fill in the blanks. Label a growing bacterial or cell culture for a brief interval with a mixture of 14C-labeled nucleosides, which would be converted to nucleotides and incorporated into . Isolate total and subject it to hydrolysis with mild . Every -terminal nucleotide will be released as a nucleoside. Separate nucleosides from nucleotides, by . Total picomoles of nucleotide in the hydrolysate divided by total picomoles of nucleoside gives the number of nucleotides incorporated per chain-which, when divided by the labeling interval (minutes) gives the growth rate of individual chains (nucleotides incorporated per chain per minute). An interesting variant of the experiment would be to carry it out with individual radiolabeled nucleosides and ask whether the chain is the same for each nucleotide.