Monomers and Polymers
Understanding monomers and polymers in AQA A-Level Biology
The variety of life, both past and present, is extensive, but the biochemical basis of life is similar for all living things.
Facts
Monomers and Polymers Definitions
- Monomers are the smaller units from which larger molecules are made.
- Polymers are molecules made from a large number of monomers joined together.
Examples of Monomers
- Monosaccharides (e.g., glucose, fructose)
- Amino acids
- Nucleotides
These monomers serve as building blocks for essential biological polymers:
- Carbohydrates (e.g., starch, glycogen)
- Proteins
- Nucleic acids (e.g., DNA, RNA)
Condensation and Hydrolysis Reactions
Condensation Reactions
A condensation reaction joins two molecules together with the formation of a chemical bond and involves the elimination of a molecule of water.
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Example: Formation of a dipeptide from two amino acids.
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Significance: This type of reaction is essential in forming complex biological polymers from monomers.
Hydrolysis Reactions
A hydrolysis reaction breaks a chemical bond between two molecules and involves the use of a water molecule.
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Example: Breaking down a disaccharide into two monosaccharides.
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Significance: Hydrolysis reactions are crucial for digestion and metabolism, allowing organisms to break down complex molecules into usable forms.
Recall
Which of the following is a monomer?
What type of reaction involves the joining of monomers with the removal of water?
Hydrolysis reactions are essential in:
Key Takeaways
- Monomers and polymers are fundamental concepts in biology that explain how complex molecules are formed and broken down.
- Recognition of condensation and hydrolysis reactions helps in understanding metabolic processes essential for life.