Chapter 23, Problem 6RAT

To determine

The correct option for the statement “How are proteins similar to starch?”

Answer to Problem 6RAT

The correct option for the statement “How are proteins similar to starch?” is option (e).

Explanation of Solution

The $\text{α-}$ amino acids are considered as the building blocks of proteins. The interaction of $-{\text{NH}}_2$ group of one amino acid with $-\text{COOH}$ group of another amino acid leads to the formation of an amide linkage. A number of amino acid units are joined with each other through $-\text{CONH}-$ linkages and results in the formation of biomolecule which is named as protein.

The starch is kind of polysaccharide and has general formula ${\left({\text{C}}_6{\text{H}}_{10}{\text{O}}_5\right)}_n$ , depending upon the source the value of $n$ varies from $200-1000$ . It is the chief food reserve material or storage polysaccharide of plants and is found mainly in seeds, roots and tubers.

Protein is consumed only when body does not get energy from the any other source. It gets converted into fat when excess of it is consumed. However, starch is the vital source of energy as it is a component of plants.

Thus, the statement which relates proteins with starch is (e).

Conclusion:

Protein and starch both are the polymers. Protein is a polymer of $\text{α-}$ amino acids whereas starch is a condensation polymer of monosaccharide units. They both are good sources of energy. Therefore, among the given statements, the statement (a) and (b) are correct.