Introduction to Biological Molecules

Overview

• Focus on monomers, polymers, and monosaccharides.
• Prepare to take notes and answer questions interactively.
• Key focus: Glucose as a monomer and its role in forming polymers like starch, cellulose, and glycogen.

Key Definitions

• Monomer: Smaller units that create larger molecules.
  • Example: Glucose
• Polymer: Made from many monomers bonded together.
  • Examples include starch, cellulose, glycogen.

Carbohydrates

• Composed of carbon, hydrogen, and oxygen.
• Classified by the number of unit structures:
  • Monosaccharides: Single unit (e.g., glucose, fructose, galactose)
  • Disaccharides: Two units (e.g., sucrose, maltose, lactose)
  • Polysaccharides: Many units (e.g., starch, cellulose, glycogen)

Monosaccharides

• Glucose is the primary monosaccharide.
  • Molecular formula: C₆H₁₂O₆
  • Structure: Hexagonal shape with 5 carbons in hexagon, 6th carbon attached.
  • Exists as two isomers:
    • Alpha-Glucose: Hydroxyl group (OH) at the bottom on carbon 1.
    • Beta-Glucose: Hydroxyl group (OH) at the top on carbon 1.

Isomers

• Isomer: Molecules with the same molecular formula but different structures.
• Importance in glucose: Alpha and beta isomers differ in the position of the hydroxyl group on carbon 1.

Summary

• Monomers are small units forming larger molecules.
• Polymers are bonded monomers.
• Carbohydrates include monosaccharides, disaccharides, and polysaccharides.
• Focus on glucose for monosaccharides, knowing its structure and role in forming polysaccharides.

Next Steps

• Review disaccharides and polysaccharides lessons.
• Practice and test your understanding of these concepts.