Question

amino acids are the building blocks of proteins. select the true statements. human body cells can synthesize some amino acids from sugar molecules. each amino acid has the same r-group. a polypeptide forms when many amino acids are linked together in a long chain. peptide bonds link amino acids together.

Explanation:

• For "Human body cells can synthesize some amino acids from sugar molecules": The human body can synthesize non - essential amino acids, and the synthesis process can involve using sugar (glucose) as a starting material through various metabolic pathways.
• For "Each amino acid has the same R - group": This is false. The R - group (side chain) is what differentiates one amino acid from another. Different amino acids have different R - groups, which give them their unique chemical properties.
• For "A polypeptide forms when many amino acids are linked together in a long chain": A polypeptide is indeed a long chain of amino acids linked by peptide bonds. When multiple amino acids are joined in a linear sequence, a polypeptide is formed.
• For "Peptide bonds link amino acids together": Peptide bonds are the covalent bonds that form between the carboxyl group of one amino acid and the amino group of another amino acid during dehydration synthesis, thus linking amino acids in a protein or polypeptide chain.

Answer:

• Human body cells can synthesize some amino acids from sugar molecules.
• A polypeptide forms when many amino acids are linked together in a long chain.
• Peptide bonds link amino acids together.