What does a molecule lose when your put two or more monomers together?

When two or more monomers are joined together to form a molecule, they typically lose a water molecule in a process called dehydration synthesis or condensation reaction. This occurs as a hydroxyl group (-OH) from one monomer combines with a hydrogen atom (H) from another, resulting in the formation of a covalent bond between the monomers and the release of water. This reaction is fundamental in the formation of larger biological macromolecules such as proteins, polysaccharides, and nucleic acids.