(7 points) Complete the "chain" task , choosing one correct one from the three proposed options (underline or circle): The primary structure of a protein is called (alpha helices,beta-pleated layers the sequence of amino acids in the polypeptide chain). The process of protein folding is called (postsynthetic modification translation, folding). If a protein contains several polypeptide chains, such a protein is called (catalytic oligomeric conjugated). In this case, each polypeptide chain is called (domain, ligand, subunit). Some proteins acquire functional activity after the formation of disulfide bridges between amino acid residues (methionine, serine cysteine).

## Step 1<br />The primary structure of a protein is the sequence of amino acids in the polypeptide chain. This is the most basic level of protein structure and is determined by the sequence of amino acids in the protein.<br /><br />## Step 2<br />The process of protein folding is called folding. This is the process by which a protein structure assumes its functional shape or conformation.<br /><br />## Step 3<br />A protein that contains several polypeptide chains is called conjugated. This term is used to describe proteins that consist of more than one polypeptide chain.<br /><br />## Step 4<br />Each polypeptide chain in a conjugated protein is called a subunit. This term is used to describe the individual components of a protein.<br /><br />## Step 5<br />Some proteins acquire functional activity after the formation of disulfide bridges between amino acid residues. The amino acid that forms these bridges is cysteine.