What is a unique characteristic of stem cells that makes them important

Anybody who knows ap biology, can you friend or message me

How is ribosomal rna useful as a molecular clock? a. a large portion of the dna ring is not vital to structure or function, allowing it to accumulate neutral mutations. b. its rate of mutation increases over time as organisms continue to evolve and differentiate from each other. c. a slow mutation rate makes it useful for determining evolutionary relationships between ancient species. d. it is only found in select organisms, making it easier to compare relationships between species that have it.

Explain how you will prioritize tasks in the medical office by immediate, essential, or optional. how will you re-prioritize when disruptions occur?