It is also found in groundwater
Answer: Turkey contains the amino acid tryptophan, which forms the basis of brain chemicals that make people tired.
During a controlled experiment, a scientist will isolate and test (D) a single variable. A conclusion, nor a mass of information can be isolated or tested. A control group is the group that would receive a placebo, so testing that would be futile.
Down syndrome, turner syndrome, Klinefelter syndrome, and fragile X syndrome.