2. Three other common elements in living organisms and an importance
or function of each are:
a. Calcium- major component of bone.
b. Phosphorus- major component of ATP
(energy carrier) and nucleic acids.
c. Nitrogen- major component of amino
acids as well as nucleic acids.
d. Iron- major component of hemoglobin
as an oxygen carrier.
e. Sodium- used in neurons for transmission
of nervous impulses.
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Slichter