Which of the following structures represents the peptide chain?

Options

A. `-overset(H)overset(|)(N)-underset(O)underset(||)(C)-underset(H)underset(|)(N)-underset(|)overset(|)(C)-NH-overset(O)overset(||)(C)-NH-`
B. `-overset(H)overset(|)(N)-underset(O)underset(||)(C)-overset(|)underset(|)(C)-overset(|)underset(|)(C)-overset(|)underset(|)(C)-overset(H)overset(|)(N)-overset(|)underset(|)(C)-overset(|)underset(|)(C)-overset(|)underset(|)(C)-`
C. `-overset(H)overset(|)(N)-underset(|)overset(|)(C)-underset(O)underset(||)(C)-overset(H)overset(|)(N)-underset(|)overset(|)(C)-underset(O)underset(||)(C)-overset(H)overset(|)(N)-underset(|)overset(|)(C)-underset(O)underset(||)(C)-overset(H)overset(|)(N)-underset(|)overset(|)(C)-`
D. `-underset(|)overset(|)(C)-overset(H)overset(|)(N)-underset(|)overset(|)(C)-underset(|)overset(|)(C)-overset(O)overset(||)(C)-underset(H)underset(|)(N)-underset(|)overset(|)(C)-underset(|)overset(|)(C)-overset(H)overset(|)(N)-underset(O)underset(||)(C)-underset(|)overset(|)(C)-underset(|)overset(|)(C)-`

Answer

C

Explanation

The pepitde linkage `(-NH-CO-)` is formed by the condensation of amino acid molecules. Two or more amino acids can link together by forming amide bonds, usually called peptide bonds. A dipeptide results when two amino acids link together by formation of a peptide bond between the `-NH_(2)` group of one and the `-CO_(2)H` of the other.

The groups symbolized by `R` and `R'` represent amino acid side chains.
Similarly, a dipeptide results when three amino acids lin together with two peptide bonds, and so on. Short chains of up to 100 amino acids are usually called polypepitdes, while the term protein is reserved for longer chains.
Thus, following structure represents the peptide chain:
`-overset(H)overset(|)(N)-underset(|)overset(|)(C)-underset(O)underset(||)(C)-overset(H)overset(|)(N)-underset(|)overset(|)(C)-underset(O)underset(||)(C)-overset(H)overset(|)(N)-underset(|)overset(|)(C)-overset(O)overset(||)(C)-`