How many possible codons exist in the genetic code? a. 3 b. 20 c. 46 d. 64

The large ground finch obtains food by cracking seeds. what is its short, strong beak an example? a) tendency toward perfection b) adaptation of a species over time c) selective use and disuse of an organ over time d) scarcity of recourses

The vaccine in a flu shot contains weakened flu viruses. how does a flu shot work with the immune system? a. it destroys lymphocytes. b. it destroys macrophages. c. it activates macrophages. d. it activates lymphocytes.

Amino acids contain the elements carbon, hydrogen, oxygen, nitrogen, and sometimes sulfur. of the 20 amino acids found in humans, 11 are called "nonessential" because they can be manufactured by the body when needed. which elements in these 11 amino acids are commonly obtained from the metabolism of sugar molecules?