Given below are two statements.

Statement I - Oxaloacetate is useful as a precursor for synthesis of aspartic acid.

Statement II - $\alpha$-ketoglutarate is useful for synthesis of glutamic acid.

In light of above statements, select the correct answer from the option given below.

In large proteins, peptide chains are much looped, twisted and folded back on themselves. The folded structure is due to the formation of________bonds

Enzymes are needed only in small quantities to catalyse reactions because

The number of amino groups in the amino acids present in amides is __________