Practicing Success
Case: Read the passage and answer the following questions Protein structure is the three-dimensional arrangement of atoms in an amino acid-chain molecule. Proteins are polymers – specifically polypeptides – formed from sequences of amino acids, the monomers of the polymer. A single amino acid monomer may also be called a residue indicating a repeating unit of a polymer. A monopeptide has one amino acid. A dipeptide has two amino acids. A tripeptide has three amino acids. A tetrapeptide has four amino acids. The complete structure of a protein can be described at four different levels of complexity: primary, secondary, tertiary, and quaternary structure. |
What type of peptides are proteins? |
Monopeptide Dipeptide Tripeptide Polypeptide |
Polypeptide |
A protein molecule is made from a long chain of these amino acids, each linked to its neighbor through a covalent peptide bond. Proteins are therefore also known as polypeptides. Each type of protein has a unique sequence of amino acids, exactly the same from one molecule to the next. |