Question

The naturally occurring amino acid that contains only one basic functional group in its chemical structure is:

• A. arginine
• B. lysine
• C. asparagine
• D. histidine

Hint:

Basic amino acids have more than one amine functional group, while neutral amino acids have only one amine group.

Answer 1

The Correct Option is C

Step 1: Understanding Functional Groups in Amino Acids 
- Amino acids contain different functional groups that determine their chemical behavior.
- Basic functional groups include amine (\(-NH_2\)) and imidazole rings. 
Step 2: Classification of Given Options 
- Arginine, Lysine, and Histidine contain multiple basic groups due to their side chains. 
- Asparagine contains only one amine group, making it the correct answer. 
Final Answer: Asparagine contains a single amine functional group, making it the correct choice.

Answer 2

Asparagine is the naturally occurring amino acid that contains only one basic functional group in its chemical structure.

Asparagine is a polar, uncharged amino acid with an amide side chain. Its chemical structure includes a single basic functional group, which is the amino group (\(-NH_2\)) attached to the alpha carbon. Unlike other amino acids such as lysine or arginine, which have additional basic groups in their side chains, asparagine’s side chain contains an amide group (\(-CONH_2\)) that is neutral and does not exhibit basic properties.

This unique structure influences asparagine's behavior in proteins, particularly in forming hydrogen bonds due to the amide side chain, contributing to protein stability and function. Hence, among naturally occurring amino acids, asparagine distinctly contains only one basic functional group.