At the beginning every heartbeat the heart is what?

Environmental impacts on evolution : mastery test

According to the rna world hypothesis, rna acted as the genetic material and catalyzed reactions in ancient cells. what conclusion can you draw from this?               a.  this implies that dna and proteins aren't essential in cells today.    b.  this implies that rna can catalyze any chemical reaction that enzymes catalyze.    c.  this implies that if a cell has a problem with its dna, its rna can compensate for the damaged dna.    d.  this implies that dna and proteins evolved after rna.

Unlike mendel's pea plants, humans can have a variety of heights, not just tall or short. what does this mean for human height? a. height is controlled by one gene b. height is controlled by more than one c. height is not genetic d. height is solely determined by whether or not you eat your vegetables