What monomers are proteins made of? What is the structure of the monomer that makes up a protein?

What monomers are proteins made of? What is the structure of the monomer that makes up a protein?

          proteins have amino acids as monomers                                    <h4 class=answerHeader>Explanation:</h4>                                      proteins are made up of 21 different L-amino acids.  these amino acids are joined together with peptide bonds.  peptide bond is a bond between a caboxylic group of one amino acid with amino group of other amino acid.  following is a figure to describe the structure of a single amino acid, where R -group is variable and can contribute for the amino acid to be neutral, acidic or basic.  next figure gives an idea of how many various amino acids are there. <br></br><img alt=enter image source here src=https://useruploads. socratic. org/7dlCTH75TbCFZbmxbXfB_amino_acid_structure. jpg></img><br></br><img alt=useruploads. socratic. org src=https://useruploads. socratic. org/7dlCTH75TbCFZbmxbXfB_amino_acid_structure. jpg></img> various amino acids<img alt=enter image source here src=https://useruploads. socratic. org/3Wt3VrWwTcWDP6j4Jl6V_amino_acids. jpg></img> <br></br><img alt=useruploads. socratic. org src=https://useruploads. socratic. org/3Wt3VrWwTcWDP6j4Jl6V_amino_acids. jpg></img>everybody is welcome for any suggestion for updating the answer<br></br>Cheerio!