3 atoms (O3) Ozone is the triatomic form of oxygen. Oxygen isn’t the only thing we breathe, we also breathe nitrogen and a whole bunch of other gases. The difference between oxygen and ozone is ozone is o3 meaning it has 3 oxygen atoms instead of just one. I really hope this helped!
An example i can think of is...
the amount of salt present in human cells cytoplasm suggests we evolved from species in the sea
The chart very nicely lays out the amino acid each codon corresponds to. You're looking for "trp" in the chart, which only appears once, beside the UGG codon. Therefore, only one codon codes for tryptophan.
Chromosems is the right answer
