Cells assemble carbohydrates through dehydration synthesis which means a(n) what molecule is removed when the monomers are bonded together

The process for connecting two monomers together is called dehydration synthesis. Dehydration means “removal of water” and synthesis means “to join together”. So in this process, two monomers are covalently bonded by the removal of a water molecule. Each organic monomer has a hydroxyl group on one side and a hydrogen on the other. When two monomers line up side by side, they will have these two functional groups facing one another. The H and the OH will break off of their respective monomers and bond forming a water molecule. This is the dehydration part of the process. Each monomer now has a carbon atom that needs to covalently bond with something, so they bind to each other forming a polymer. That is the synthesis part of the process. 

Cotton was the very first