Why do organisms found at low temperatures have membrane proteins with a higher percentage of alpha helices compared to beta sheets?

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 the number of similarities between the embryos from early stage to late stage is used as evidence of a common ancestry

Match each term to its best definition? sedimentary depositional enviornment