Tag: biological importance of sodium and potassium

Questions Related to biological importance of sodium and potassium

Which of the following metals is required as a cofactor by all enzymes utilizing ATP in phosphate transfer?

  1. K

  2. Ca

  3. Na

  4. Mg


Correct Option: D
Explanation:

Mg binds to phosphate group in ATP thus making a complex that catalyses phosphate transfer. 

The main constituents of pearl are:

  1. ammonium sulphate and sodium carbonate

  2. aragonite are conchiolin

  3. calcium carbonate and magnesium carbonate

  4. calcium oxide and ammonium chloride


Correct Option: B
Explanation:

The chief component of the nacre that constitutes the pearl is aragonite $(CaCO _3)$. Nacre also contains a small amount of conchiolin, a hornlike organic substance (albuminoid) that is the main constituent of the mollusk's outer shell.

Which of the following statements is/are false?

  1. The halides of beryllium are electron deficient and are polymeric with halogen bridges.

  2. $BeF _2$ is very soluble in water owing to high solvation energy of Be but fluorides of other alkaline earth metals are almost insoluble.

  3. CaO, SrO and BaO react exothermically with water forming soluble hydroxides.

  4. The bicarbonates of alkaline earth metals are only stable in solutions.


Correct Option: A,B,C,D

Select correct statement(s).

  1. $Mg^{2+}$ ions are necessary for the activation of phosphate transfer enzymes.

  2. Mg is present in chlorophyll of green plants.

  3. Mg is present in chlorophyll used in photosynthesis in green plants.

  4. All the above are correct statements


Correct Option: D