See if any of the organisms lived before the others by measuring the age
of their fossils using some means, like radioactive dating.
Bacteria makes up most of our gut flora
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Pollution on land gets in our river and ocean through air and people throwing their trash in the river and oceans
Amino acids are molecules that have a carboxylic acid group and an
amine, attached to a specific carbon atom known as the α carbon. There are 20
amino acids, and they are different from each other, in the sense that each has
a different side chain, known as the R-group and this R-group is attached to
the α carbon.
