Explain the change in RNA concentration between 60% and 80% of the time spent as a pupa.

Explain the change in RNA concentration between 60% and 80% of the time spent as a pupa.

• A. RNA is used for making proteins for new tissues, so concentration rises
• B. RNA concentration decreases due to less transcription
• C. RNA is degraded to release energy
• D. RNA remains at a constant level

Answer: (A)

RNA concentration rises because, during late pupation, the insect is actively building new adult tissues and organs. RNA, especially messenger RNA, carries the instructions for making the proteins those tissues need. As cells differentiate and tissues form between 60% and 80% of the pupal period, transcription ramps up to supply ample mRNA for protein synthesis, so RNA levels increase. Degrading RNA for energy isn’t the main role here, and staying constant would imply no extra protein production, which doesn’t fit the active tissue formation happening in this window.

RNA concentration rises because, during late pupation, the insect is actively building new adult tissues and organs. RNA, especially messenger RNA, carries the instructions for making the proteins those tissues need. As cells differentiate and tissues form between 60% and 80% of the pupal period, transcription ramps up to supply ample mRNA for protein synthesis, so RNA levels increase. Degrading RNA for energy isn’t the main role here, and staying constant would imply no extra protein production, which doesn’t fit the active tissue formation happening in this window.