What kind of bond primarily holds together the structures of proteins?

Proteins are composed of amino acids linked together in a specific sequence, and the bond that primarily connects these amino acids in a protein is called a peptide bond. A peptide bond is a type of covalent bond formed between the carboxyl group of one amino acid and the amino group of another. Through a condensation reaction, a molecule of water is released, resulting in the formation of the bond that creates a dipeptide and, as additional amino acids are added, ultimately a polypeptide or protein.

While there are other types of bonds, such as hydrogen bonds that help stabilize protein structure (particularly in secondary and tertiary structures), and ionic bonds which can contribute to the overall stability of protein conformation, the specific linkage between amino acids is through peptide bonds. This is fundamental in forming the primary structure of proteins, which is crucial for their overall function and shape.