Macromolecules – iGCSE Chemistry (Triple) CAIE Revision

Macromolecules are large complex molecules, such as proteins or nucleic acids, composed of smaller units called monomers.
The word “macromolecule” derives from “macro-“, meaning large, and “molecule”, the smallest unit of a compound that retains its chemical properties.

Macromolecules are formed by repeated linking of monomers through a process called polymerisation.
The monomers are bonded together through covalent bonds, resulting in a long, chain-like molecule.
Many macromolecules, such as proteins and nucleic acids, have a complex 3D structure that is essential for their function.

There are four main types of biological macromolecules: carbohydrates, proteins, nucleic acids, and lipids.
Carbohydrates, like starch or cellulose, are made up of monomers called monosaccharides, such as glucose.
Proteins are made up of monomers called amino acids. Proteins are essential for structure, function, and regulation of body’s tissues and organs.
Nucleic acids, like DNA and RNA, are made up of monomers called nucleotides that carry genetic information.
Lipids are not true polymers as they are made up of glycerol and fatty acids. They include fats, oils, waxes, phospholipids, and steroids.

Macromolecules generally have high molecular weights and their physical and chemical properties are largely determined by the functional groups they contain.
Due to their large size, many macromolecules are not soluble in water.
Macromolecules like proteins and nucleic acids play crucial roles in biological processes.
Many macromolecules have a complex, specialized structure that allows them to perform their specific tasks within an organism.