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Biology 2nd Baccalaureate

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1.2.2. Secondary bioelements

Secondary bioelements

The secondary bioelementos have different functions.

The most abundant are Na, K, Mg and Ca.

  • The Na+, K+ and Cl- ions, the most abundant in the internal environment and within the cells, intervene in the maintenance of the degree of salinity and in the balance of electrical charges on both sides of the plasma membrane.
  • Ions Na+ and K+, involved in the transmission of nerve impulses.
  • The calcium as carbonate (CaCO3), constitutes the shells of mollusks and skeletons of many other animals, and as ion (Ca2+) acts in many reactions, as the mechanisms of muscle contraction, permeability cell membranes, blood clotting, etc.
  • The magnesium is part of many enzymes (cofactor) and the pigment chlorophyll. It is also involved in many reactions, such as ATP synthesis and degradation, DNA replicationRNA synthesis, etc.


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