AQA A Level Biology: Monomers and Polymers Flashcards
What is a monomer?
A monomer is a small, basic molecular unit that can join with other monomers to form a polymer.
What is a polymer?
A polymer is a large molecule made up of many monomers joined together by condensation reactions.
Name 3 biological polymers and their monomers.
- Carbohydrates – Monomer: Monosaccharides (e.g., glucose).
- Proteins – Monomer: Amino acids.
- Nucleic acids – Monomer: Nucleotides.
What type of reaction forms polymers?
Condensation reaction, which removes a water molecule and forms a bond between monomers.
What type of reaction breaks down polymers?
Hydrolysis reaction, which adds a water molecule to break bonds between monomers.
What is a condensation reaction?
A reaction where two molecules combine, forming a larger molecule and releasing a molecule of water.
What is hydrolysis?
A reaction that breaks down polymers into monomers by adding a molecule of water.
Give an example of a condensation reaction in biology.
Formation of a peptide bond between amino acids to create a polypeptide.
Give an example of a hydrolysis reaction in biology.
Breakdown of starch into glucose by adding water and using enzymes like amylase.
What is a disaccharide?
A molecule formed from two monosaccharides joined by a glycosidic bond through a condensation reaction.
Name 3 common disaccharides and their monomers.
- Maltose – Glucose + Glucose.
- Sucrose – Glucose + Fructose.
- Lactose – Glucose + Galactose.
What is a glycosidic bond?
A covalent bond formed between two monosaccharides during a condensation reaction.
How are polypeptides formed?
Polypeptides are formed by condensation reactions between amino acids, resulting in peptide bonds.
How are polynucleotides formed?
Polynucleotides are formed by condensation reactions between nucleotides, creating phosphodiester bonds.
Why are hydrolysis and condensation reactions important in biological systems?
They allow the formation and breakdown of macromolecules essential for life, such as carbohydrates, proteins, and nucleic acids.
