Which defines a codon in DNA or mRNA?

pair of nucleic acid and sugar

pair of phosphate and sugar

three-base code

two-base code

Ecologist have observed a sharp increase of sulfur dioxide in the air . what might be a possible consequence of excessive sulfur dioxide in the air ? a. acid rain b. ozone layer depletion c.ozone layer hole d.increase in sea levels

A60-tooth gear is connected to a 72-tooth gear.if the smaller gear turns 12 times,how many turns does the larger gear make?

Ascientist is conducting an investigation that involves water, silver, carbon dioxide, and oxygen gas which group of statements best describes all of the materials he is using in the investigation?