You incubate eukaryotic cells for 30 minutes in [³H]uridine and then immediately kill the cells and extract the RNA. Where does the radiolabel appear after this experiment? A)in larger molecular weight RNAs in the nucleus B)in smaller molecular weight RNAs in the mitochondria C)in smaller molecular weight RNAs in the cytoplasm D)in larger molecular weight RNAs in the mitochondria E)in moderately sized RNAs in the Golgi complex

Question

Quizplus · Accepted Answer

The radiolabeled uridine is incorporated into newly synthesized RNA. In eukaryotic cells, transcription of larger molecular weight RNAs, such as precursor mRNAs and ribosomal RNAs, occurs in the nucleus. These RNAs are then processed and either remain in the nucleus or are exported to the cytoplasm. Given the short incubation time, the label would predominantly be found in larger molecular weight RNAs in the nucleus before significant processing or export occurs.

You Incubate Eukaryotic Cells for 30 Minutes in [3H]uridine and Then

You Incubate Eukaryotic Cells for 30 Minutes in [³H]uridine and Then