Features of the chemical composition of the cell
Cell chemical elements
Living organisms and bodies of inanimate nature consist of the same chemical elements. This fact speaks of the relationship between animate and inanimate nature. The cells of different living organisms contain atoms of the same chemical elements, which confirms the unity of all living organisms.
Of the currently known more than 115 elements, about 80 are found in the composition of the cell.
All elements, according to their content in living organisms, are divided into three groups:
- macronutrients – the content of which exceeds 0.001% of body weight.
- 98% of the mass of any cell accounts for four elements (they are sometimes called organogens): – oxygen (O) – 75%, carbon (C) – 15%, hydrogen (H) – 8%, nitrogen (N) – 3%. These elements form the basis of organic compounds (and oxygen and hydrogen, in addition, are part of the water, which is also contained in the cell). About 2% of the cell mass accounts for eight more macronutrients: magnesium (Mg), sodium (Na), calcium (Ca), iron (Fe), potassium (K), phosphorus (P), chlorine (Cl), sulfur (S );
- The rest of the chemical elements are contained in the cell in very small amounts: trace elements – those that account for from 0.000001% to 0.001% – boron (B), nickel (Ni), cobalt (Co), copper (Cu), molybdenum (Mb), zinc (Zn), etc .;
- ultramicroelements – the content of which does not exceed 0.000001% – uranium (U), radium (Ra), gold (Au), mercury (Hg), lead (Pb), cesium (Cs), selenium (Se), etc.
Living organisms are capable of accumulating certain chemical elements. So, for example, some algae accumulate iodine, buttercups – lithium, duckweed – radium, etc.
Elements in the form of atoms are part of the molecules of inorganic and organic compounds of the cell.
Inorganic compounds include water and mineral salts.
Organic compounds are characteristic only of living organisms, while inorganic compounds exist in inanimate nature.
Organic compounds include carbon compounds with molecular weights from 100 to several hundred thousand.
Carbon is the chemical basis of life. It can bond with many atoms and their groups, forming chains, rings that make up the skeleton of organic molecules of different chemical composition, structure, length and shape. They form complex chemical compounds that differ in structure and function. These organic compounds that make up the cells of living organisms are called biological polymers, or biopolymers. They make up more than 97% of the dry matter of the cell.