Condensation, Hydrolysis and the Polymers of Life
Carbohydrates, proteins and nucleic acids are all polymers joined by condensation and taken apart by hydrolysis. One bond-making rule covers three families of molecule.
What a learner can do afterwards
- States what a condensation reaction removes and what a hydrolysis reaction adds.
- Names the monomer and the bond for a carbohydrate, a protein and a nucleic acid.
- Works out how many water molecules were released when a chain of a given length formed.
1 · Read
Living things build giant molecules by chaining small ones together. Joining two pieces is called a condensation reaction, and it releases one molecule of water as the bond forms.
Three families form true polymer chains of repeating pieces, and each pair is its own team. Carbohydrates link sugars with glycosidic bonds, proteins link amino acids with peptide bonds, and nucleic acids link nucleotides with phosphodiester bonds. Memorise each pair as a team and the names stop slipping.
Here is the counting trick: every new link releases one water, and links always number one fewer than pieces. A chain of 100 pieces has 99 links, so it released 99 waters when it formed and needs 99 waters to break fully apart. A chain of twelve monomers released 11 waters.
Breaking apart is hydrolysis. It spends one water molecule to snap one bond open. Digestion uses hydrolysis in your gut to chop starch, protein and DNA into small pieces that blood can absorb.
Breaking needs the same link count as building. A chain of 100 pieces has 99 links, so full hydrolysis needs 99 waters, one per bond.
Nucleic acids are the third team. Nucleotides link through phosphodiester bonds. Your gut snaps those bonds when it digests DNA back into nucleotides.
One water out per link made, one water in per link broken, with links always one fewer than pieces.
Rewritten readings were written for this dataset.
2 · Watch
En anglaisTake it off screen
Where it sits
Where this leads
Jobs that lean on this skill. Follow one to see everything it is built on.
8 questions wait behind this lesson, each with its answer explained. Every answer feeds the sky: stars light as they are learned, and dim when it is time to come back.