NEET 2020 Chemistry Question 122 Solution

In the s-block elements chapter, NCERT presents an explicit section detailing the biological roles of sodium and potassium ions in human physiology.

NCERT states verbatim: "Potassium ions are the most abundant cations within cell fluids, where they activate many enzymes, participate in the oxidation of glucose to produce ATP and, with sodium, are responsible for the transmission of nerve signals."

The operating concentration gradient across the neuronal membrane (high $$K^+$$ inside, high $$Na^+$$ outside) is maintained by the active $$Na^+/K^+$$ pump, which consumes more than one-third of total resting ATP in a resting animal to propagate nerve impulses.

- Calcium ($$Ca^{2+}$$): Essential for neuromuscular excitability, blood clotting, and bone mineralization. - Iron ($$Fe^{2+}/Fe^{3+}$$): Part of haemoglobin and cytochromes for electron transport. - Copper ($$Cu^{2+}$$): Component of cytochrome c oxidase and tyrosinase. Thus, Potassium is uniquely described by all three statements.