Answer:
When a molecule moves down its concentration gradient is it participating in passive transport; moving up the concentration gradient requires energy making it Answer:active transport
<span>The RNA world is the hypothesized format of chemical life that existed prior to our current DNA and RNA world. In the RNA world, RNA molecules formed in the primordial soup and began to evolve by self-replication and mutation. This led to increased complexity, natural selection of "better" RNA and diversification of RNA based life.</span>
