The first genetic material on earth was probably ________.
A) DNA produced by reverse transcriptase from abiotically produced RNA
B) DNA molecules whose information was transcribed to RNA and later translated in polypeptides
C) self-replicating RNA molecules
D) oligopeptides located within protobionts
Answer:
C) self-replicating RNA molecules
Explanation:
RNA molecules are considered to be the first genetic material that evolved on the earth. Assembly of nucleotides gave rise to single stranded RNA molecules that could catalyze various processes. These RNA molecules were able to replicate themselves. In this way, the self-replicating RNA molecules served as the first genetic material. Later, the accumulation of several mutations such as the evolution of thymine base from uracil and deoxyribose sugar from the ribose sugar gave rise to DNA.
