Iron in Hemoglobin (Hb)

• Hb is the iron-containing oxygen-transport metalloprotein found in our blood which is responsible for the red colour of blood. About 70% of our body’s iron is found in hemoglobin.

• Its level varies from person to person – males (13.5-17.5 g/dL) have higher levels of hemoglobin than females (12-15.5 g/dL) [11].

Sodium-Potassium (Na+/K+) pump:

• Sodium-potassium pump is an example of primary active transport where the movement of ions across the cell membrane is against the concentration gradient for which the energy released during respiration (ATP) is used. It is a protein pump found mostly in the cell membrane of neurons.

• In this biological pump, the sodium and potassium ions move against the concentration gradients. A difference in charges causes a voltage across the membrane known as membrane potential, which is important for the conduction of electrical impulses along nerve cells.

To run the pump, magnesium ions (Mg2+) also play a crucial role by catalysing hydrolysis of ATP and reactivating the pump.

The sodium-potassium pump plays a crucial role in various physiological processes:
 

• Necessary for the kidney to filter waste products in the blood, reabsorb amino acids, reabsorb glucose, regulate electrolyte levels in the blood, and to maintain pH.

• Neurons need it to reverse postsynaptic sodium flux to re-establish the potassium and sodium gradients which are necessary to fire action potentials.

Elements in Enzymes:

• Zinc (Zn²⁺⁾ in Carbonic anhydrase: Carbonic anhydrase is a Zn²⁺- containing metalloenzyme that catalyses the interconversion between CO₂, H₂O and the dissociated ions of carbonic acid. Carbonic anhydrases are enzymes found in red blood cells, gastric mucosa, pancreatic cells, and renal tubules. The enzyme also plays crucial functions in the formation of hydrochloric acid by the stomach.

• Cobalt (Co³⁺⁾ in Vitamin B12: Cobalt is a trace element essential to mammals in the form of vitamin B 12 i.e., cobalamin. The adult human body contains approximately 1 mg of cobalt and 85% of which is available in the form of vitamin B 12. Vitamin B12 or cobalamin represents only a small fraction, which is essential for the prevention of anaemia in humans. Vitamin B
  12 is involved in the metabolism of proteins, phospholipids and neurotransmitters. It also plays a major role in the production of genetic material. Cobalamin serves a vital role in the metabolism of fatty acids essential for the maintenance of myelin sheath. Deficiency of vitamin B 12 enzyme leads to anaemia, gastrointestinal disturbances and neurological impairment. It may also result in irregular destruction of the myelin sheath, which leads to paralysis and death.