The answer is the Precapillary sphincter
If I am not wrong, I believe the answer is Producers. The reason as to why I say that producers is the answer is because in every food chain, there needs to be a base. That base is what provides the starting energy that will later on move up in the food chain.
<span> LOOK up Negative Regulations E. Coil
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Because it can analyze of what we are made of and who were our ancestors by studying our DNA
