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Inorganic ions: iron, hydrogen, sodium and phosphate

Inorganic ions: iron, hydrogen, sodium and phosphate

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Inorganic ions: iron, hydrogen, sodium and phosphate

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Summary

Inorganic ions: iron, hydrogen, sodium and phosphate

In a nutshell 

Inorganic ions play a key role in many biological processes. They are especially important for haemoglobin, enzymes, co-transport, ATP and nucleotides. 



Inorganic ions

​​Definition

Ions are atoms or a group of atoms that have an electric charge. 


Positively charged ions are known as cations and negatively charged ions are called anions. Inorganic ions do not contain any carbon and they can be found in solution, in cells cytoplasms and in body fluids of organisms. The properties of the inorganic ions determine their specific role. There are four inorganic ions you need to know about: iron ions, hydrogen ions, sodium ions and phosphate ions.



Iron ions

Haemoglobin is a protein made up of four polypeptide chains each with an iron ion (Fe2+Fe^{2+}Fe2+) in the centre. It is the iron ion that binds the oxygen. When Fe2+Fe^{2+}Fe2+ binds oxygen it becomes Fe3+Fe^{3+}Fe3+ until the oxygen is released. ​



Hydrogen ions

Hydrogen ions (H+H^+H+) determine pH as pH is calculated using the concentration of H+H^+H+ in the environment. More hydrogen ions mean the lower the pH and the more acidic the environment. pH is important for enzyme-controlled reactions as enzymes can be denatured at extreme pHs.​



Sodium ions

Sodium ions (Na+Na^+Na+) are involved in transport across membranes. Large molecules such as glucose and amino acids are transported across cell-surface membranes alongside a sodium ion. This is known as co-transport. 

​


Phosphate ions

Phosphate ions (PO4 3−PO_4\space ^{3-}PO4​ 3−) are key components in DNA, RNA and ATP. The phosphate ions are known as phosphate groups when attached to another molecule and the bonds between phosphate groups are what store energy in ATP. In DNA and RNA the phosphate groups allow nucleotides to join up.


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Ionic bonding: properties of compounds and naming

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Ionic bonding: properties of compounds and naming

Ions and their formation

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Ions and their formation

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Inorganic ions: iron, hydrogen, sodium and phosphate

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Inorganic ions: iron, hydrogen, sodium and phosphate

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FAQs - Frequently Asked Questions

What is the role of sodium ions in the body?

Sodium ions are involved in transport across membranes. Large molecules such as glucose and amino acids are transported across cell-surface membranes alongside a sodium ion. This is known as co-transport.

What is the role of iron in oxygen transport?

Haemoglobin is a protein made up of four polypeptide chains each with an iron ion in the centre. It is the iron ion that binds the oxygen.

What are inorganic ions?

Inorganic ions are atoms or a group of atoms that have an electric charge and do not contain any carbon.

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