What are the 4 base pairs associated with rna?

Explain the source of radioactivity in uranium in earth’s crust by which it produces nuclear radiation

What mistake did john needham make that caused him to conclude that spontaneous generation for microorganisms occurred? a. he re-contaminated his boiled broth solutions. b. he destroyed the vital force in the solutions. c. he did not boil his broth solutions, only warmed them. d. he failed to seal his flasks of boiled broth. e. he allowed his assistant to conduct the experiment which he did not monitor closely.

Ineed a little . why do you think there is a basic difference between the kinds of fertilization most common in aquatic and terrestrial animals?