Proteins are polymers of $\alpha$-amino acids which are joined to each other by:
Show Hint
- Covalent Bond
- Peptide Bond
- Glycosidic Bond
- Coordinate Bond
The Correct Option is B
Solution and Explanation
Macromolecular polymers in biology are synthesized by linking specific monomer units together through specialized condensation bonds.
Step 2: Meaning
Proteins are biological polyamides constructed entirely from sequences of $\alpha$-amino acid monomers.
Step 3: Analysis
When two $\alpha$-amino acids condense, the carboxyl group ($-COOH$) of the first amino acid reacts with the amino group ($-NH_2$) of the second amino acid.
A molecule of water is eliminated, creating an amide linkage ($-CO-NH-$).
While this is technically a type of covalent bond, in the specific context of biochemistry
and protein structure, this specialized amide bond linking amino acids is uniquely defined as a "peptide bond."
Step 4: Conclusion
Therefore, the most precise and biologically accurate term is the peptide bond.
Final Answer: (B)
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