Protein synthesis consumes four high-energy phosphate bonds per added amino acid. Transcription consumes two high energy phosphate bonds per added nucleotide. Calculate how many protein molecules will have been made from an individual mRNA at the point when the energy cost of translation is equal to the energy cost of transcription. Assume that the nucleotides in the coding portion of the mRNA constitute 5% of the total that are transcribed.

30 protein molecules per mRNA molecule

Explanation:

In this problem, it is necessary to have into account that the transcriptional process requires six (6) phosphate bonds to synthesize one (1) codon (i.e, each three nucleotides), and also discards 95% more energy to make mRNA, it means 19 times this amount of energy >> 6 x 19 = 114 bonds. In consequence, transcription requires 120 phosphate bonds (6 + 114 = 120), while translation requires four (4) phosphate bonds per codon. From this deduction, it is possible to find the number of protein molecules synthesized with regard to the energy cost of the translation process and the transcriptional process >>> 120 bonds (transcription) /4 bonds (translation) = 30 protein molecules.