Dehydration synthesis and hydrolysis build monomers into polymers and vice versa

Question

How do dehydration synthesis amd hydrolysis build monomers into polymers and vice versa?

Answer 1

In all cases of condensation, molecules with projecting -H atoms  are linked to other molecules with projecting  -OH  groups, producing H2O,  ( H.OH ) also known as water, which then moves away from the original molecules.

A-H + B-OH   -->  A-B   +  H2O

In carbohydrates, the sub-units to be joined are monosaccharides like glucose.  Both of the groups which combine are -OH groups, (even though there are many single -H atoms on a glucose molecule). Joining two  -OH groups with the removal of  H2O results in a disaccharide containing an   -O-  bridge between the 2 monosaccharide units.

Hydrolysis is the opposite to condensation. A large molecule is split into smaller sections by breaking a bond, adding -H to one section and -OH to the other.

The products are simpler substances. Since it involves the addition of water, this explains why it is called hydrolysis, meaning splitting by water.

A-B   +  H2O  -->  A-H + B-OH