Why are lipids not considered polymers?

In order to enable the subunits to continue constructing longer macromolecules on either end, polymers are chains of subunit molecules that are similar to one another.

Lipids, on the other hand, only grow in one direction; they are chains of carbohydrates that are chemically bonded (for example, by dehydration) to one another into a new, larger molecule. Lipids also have a distinct starting molecule that is different from the subunits.

Certain lipids have a natural limit because additional hydrocarbons may not naturally dehydrate at the open end; cholesterol is one example of a lipid that has this property. Additionally, a polymer has no natural fixed size and must be terminated by a process in living organisms.

By taking one hydrogen atom from one molecule and one OH atom from the other, dehydration is the process of forming a bond between two molecules to form a new, larger molecule. This results in the creation of one free water molecule.

Lipids are not considered polymers because they are not built from repeating monomeric units like proteins, nucleic acids, and carbohydrates. While lipids do have various structures and functions, they typically do not exhibit the repetitive, chain-like structure characteristic of polymers.