Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
A possible evolutionary pathway of the life system, which comprised genes, genetic code (codons for amino acids), and proteins, and originated from the [GADV]-protein world. Solid arrows, dotted arrows and a broken arrow indicate directions of evolutionary pathways of the life system, the expression of genetic information, and the time flow, respectively.
