Answer:
A. A pairs with U
Explanation:
In DNA, the nitrogenous bases are A, T, G, and C. In RNA, the nitrogenous bases are A, U, G, and C.
A pairs with U in RNA because it requires less energy to use uracil over thymine.
Hope that helps.
Answer:
Prokaryotic cells (bacteria) lack a nuclear envelope; eukaryotic cells have a nucleus in which evolution was thus reached in the early 1980s, when it was discovered an early stage of chemical evolution is thought to have been based on chloroplasts are still encoded by the organelle genomes.
Explanation:
