1.) what is one distinguishing feature of chordates? What are some examples of chordates? 2.) Do vertebrates have an endoskeleton or exoskeleton? What are some examples of vertebrates?

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.

Ronald wants to see if a new shower cleaner works better in removing soap than his old cleaner. he uses the new cleaner on one half of the shower tiles and his old cleaner on the other half. identify the independent and dependent variables in this experiment. enter your answer in the space provided.

Aparent with freckles is crossed with a parent without freckles. the punnett square shows the possible genotypes and phenotypes of the offspring. which statement accurately describes the probability of phenotypes? a. the offspring are more likely to have freckles. b. the offspring are more likely to have no freckles. c. the likelihood of the offspring having freckles and not having freckles is the same. d. the likelihood of the offspring having freckles and not having freckles cannot be determined.