During transcription, what happens to the RNA polymerase if a repressor protein attaches to the operator? A. It begins transcription.
B. It begins translation.
C. It cannot attach to enzyme 1.
D. It cannot attach to the promoter.

How can a geological time scale best be reconstructed? a) comparing vestigial structures in living species b) comparing homologous structures in living species c) examining homologous structures in fossil remains d) examining the written records of scientists from past cultures

The cluster of developing cells from conception until birth is called an

Hector is back from his morning run and is feeling light-headed because his energy is depleted which food item will provide him with a quick source of carbohydrates