In animals, what types of cells differentiate from the outer layer of cells? a. Middle layer?
b. Inner layer?

Which group of chordates does  notpossess true backbones?                 a.  birds      b.  frogs and toads      c.  lampreys      d.  crocodilians

This class has taught you that the use of science and medicine in practical ways has become an international endeavor. one of the greatest examples of an international science accomplishment is which allows the profiling of human dna, useful not only to science but also medicine. a) forensic science b) the fbi c) the human genome project d) bioterrorism

14. which of the following codons code for threonine? a. ucg b. ugu c. cga d. aca