The chemical elements that form the substances of living cells can be divided into two groups:
1) Macronutrients – are contained in cells in large quantities, they include carbon, hydrogen, oxygen, nitrogen, make up 98% of the total cell content.
2) Microelements – are contained in cells in a very small amount, they include iron, manganese, zinc, copper, iodine, fluorine, etc., make up no more than 0.8% of the total cell content.
The intermediate position is occupied by elements of sodium, calcium, phosphorus, sulfur, chlorine and magnesium, their content in the cell is approximately 1.9%. Therefore, the division of the chemical elements of the cell into micro and macro elements is rather arbitrary.
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