It is estimated that of human dna encodes protein. a) about fifty percent b) less than five percent c) more than ninety-five percent d) between eighty-five to ninety-five percent

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

Astudent observes a star from two positions of earth in its orbit, in summer and winter, and measures the change in the position of the star. which of these can be best calculated by this method?

How many chromosomes does each human cell contain? a. 23 chromosomes b. 26 chromosomes c. 43 chromosomes d. 46 chromosomes