2.2.b Define the terms monomer, polymer, macromolecule, monosaccharide, disaccharide and polysaccharide.
Below are some important definitions that will come in handy for your GCE CIE Biology exams:
Macromolecule: a large biological molecule such as a protein, polysaccharide or nucleic acid.
Monomer: a relatively simple molecule which is used as a basic building block for the synthesis of a polymer; many monomers are joined together to make the polymer, usually by condensation reactions; common examples of molecules used as monomers are monosaccharides, amino acids and nucleotides.
Polymer: a giant molecule made from many similar repeating subunits joined together in a chain; the subunits are much smaller and simpler molecules known as monomers; examples of biological polymers are polysaccharides, proteins and nucleic acids.
Monosaccharide: a molecule consisting of a single sugar unit with the general formula (CH2O)n.
Disaccharide: a sugar molecule consisting of two monosaccharides joined together by a glycosidic bond.
Polysaccharide: a polymer whose subunits are monosaccharides joined together by glycosidic bonds.
⚠️⚠️ If a a ‘define’-type question arises in the GCE CIE Biology exam, make sure to precisely explain the meaning of the word, concept or phrase.
Yaaas! Done deal! 🤘
References:
Jones, M., & Parkin, M. (2018). Cambridge International AS and A Level Biology. Cambridge: Cambridge University Press.