The human body has many levels of structural organization. of the level is the lowest in the hierarchy. can any one fill in the black

Chemical  level

There are six levels of structural organization of a human body. Of these, the chemical level is the lowest in the hierarchy which includes atoms and molecules that are essential in maintaining life.

Atom is the smallest part of elements such as carbon, hydrogen, oxygen, nitrogen, calcium, potassium and sodium. Molecules are the chemical combination of two or more atoms.  

70 % i think is the answer.

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