Question

complete the table to compare these structures.
amino acid nucleotide
is a building block of proteins
contains carbon
has a carboxyl group

Explanation:

• Amino acid:
• Proteins are polymers made up of amino acid monomers. So, amino acids are building blocks of proteins.
• Amino acids have a general formula \(R - CH(NH_2)-COOH\). They contain carbon in the \(R\) group, the amino \((-NH_2)\) group - containing carbon in some \(R\) groups (e.g., in alanine \(R = -CH_3\)), and the carboxyl \((-COOH)\) group.
• The carboxyl group \((-COOH)\) is a defining part of the amino acid structure.
• Nucleotide:
• Nucleotides are the building blocks of nucleic acids (DNA and RNA), not proteins.
• A nucleotide has three components: a nitrogen - containing base (which has carbon, e.g., adenine \(C_5H_5N_5\)), a pentose sugar (a carbohydrate with carbon, hydrogen, and oxygen, e.g., ribose \(C_5H_{10}O_5\) or deoxyribose \(C_5H_{10}O_4\)), and a phosphate group (\(-PO_4^{3 -}\)). So, it contains carbon.
• A nucleotide does not have a carboxyl \((-COOH)\) group. Its acidic property comes from the phosphate group.

Answer:

• Amino acid: Is a building block of proteins (✔), Contains carbon (✔), Has a carboxyl group (✔)
• Nucleotide: Is a building block of proteins (✖), Contains carbon (✔), Has a carboxyl group (✖)