There aren't enough oxygen molecules in the air are higher altitudes
It is a vein and it carries the blood back to the heart through the vena cavas so the blood can be reoxygenated
Answer:
The correct answer is option E. "nucleotides can only be added to an available 3'-OH group on the transcript terminus".
Explanation:
RNA synthesis is catalyzed by an enzyme called RNA polymerase. RNA polymerase always catalyze the synthesis of new RNA from 5' to 3' because nucleotides can only be added to an available 3'-OH group on the transcript terminus. This has been confirmed in labeling experiments with γ-32P substrates which establish the presence of a triphosphate moiety in transcripts with either pppG or pppA.
Answer:
Mitochondria and chloroplasts likely evolved from engulfed bacteria that once lived as independent organisms. At some point, a eukaryotic cell engulfed an aerobic bacterium, which then formed an endosymbiotic relationship with the host eukaryote, gradually developing into a mitochondrion. (nature.com)
Explanation:
