In a model of earth's layers that is determined by physical properties, how might the atmosphere be classified? would it be part of the lithosphere or a seperate layer?

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.

Which statement best describes how the nucleus, the rough endoplasmic reticulum, and ribosomes interact during protein synthesis?

Which of the following was not a major animal on land during the carboniferous period? amphibians insects both a and b none of the above