Monomers are small molecules composed of two or more elements, such as carbon, hydrogen, oxygen, nitrogen, and phosphorus. Glucose, amino acids, and nucleotides are monomers that occur naturally. The table shows the structure of these monomers. Glucose Amino Acid Nucleotide Monomers are the building blocks of larger molecules, called polymers. For example, proteins are composed of chains of amino acids that are linked together. Cellulose is a polymer that makes up plant cell walls. Cellulose is made from a chain of C6H10O5 molecules. Which monomers are most likely used to produce cellulose? Why?