A) ammonia
B) carbon dioxide
C) hydrogen
D) simple carbohydrates

A) By thermonuclear reactions that normally take place in stars.
B) In explosions of stars.
C) By the action of cosmic rays outside the stars since the formation of the galaxy.
D) All of the choices are true
E) None of the choices; all the elements were present from the initial Big Bang.

A) was a critical component of the Miller-Urey experiment.
B) requires a protein as a catalyst.
C) helped dispel the vital force theory.
D) supported the vital force theory.