In the nitrogen cycle, the bacteria that replenish the atmosphere with N2 are Naim 12:34 AP Biology In the nitrogen cycle, the bacteria that replenish the atmosphere with N2 are A) Rhizobium bacteria. B) nitrifying bacteria. C) denitrifying bacteria. D) methanogenic protozoans. E) nitrogen-fixing bacteria. Answer: C Learn More : Share this Share on FacebookTweet on TwitterPlus on Google+