Biomolecules: Quick Reference

Overview

  • Biomolecules (macromolecules) essential for cell and organism structure and function: carbohydrates, lipids, proteins, nucleic acids.
  • Monomer = building block; each biomolecule class has a relevant monomer.

Carbohydrates

  • Monomer: monosaccharide (example: glucose).
  • Disaccharide: two monosaccharides (example: maltose).
  • Common ending -ose indicates a carbohydrate (glucose, maltose, lactose, sucrose, fructose).
  • Polysaccharide: many monosaccharides (examples: starch in plants, glycogen in animals).
  • Structural roles: cellulose in plants; chitin in fungi and insect exoskeletons.
  • Energy: glucose is used in cellular respiration to produce ATP.
  • Quick/layered energy storage: carbohydrates provide fast energy; energy can be stored as polysaccharides.
  • Note: cellulose is structural; chitin is also in exoskeletons.
  • Cellular respiration (example):
    \mathrm{C6H{12}O6} + 6\,\mathrm{O2} \rightarrow 6\,\mathrm{CO2} + 6\,\mathrm{H2O} + \text{ATP energy}

Lipids

  • Monomers/building blocks: glycerol and fatty acids (various types share hydrophobic character).
  • Hydrophobic or largely hydrophobic; not water soluble.
  • Membranes: phospholipid bilayer forms cell membranes.
  • Energy storage: long-term energy source.
  • Insulation: thermal and electrical (e.g., myelin sheath).
  • Hormones: many lipids act as chemical messengers.
  • Types: triglycerides, phospholipids, steroids.
  • Examples: butter, olive oil.

Proteins

  • Monomer: amino acids.
  • Structure: many proteins form tissues (e.g., muscle, hair, collagen).
  • Membrane role: embedded channels in cell membranes.
  • Cell signaling: receptors for coordinating cellular actions.
  • Enzymes: most enzymes are proteins.
  • Immunity: antibodies are proteins.
  • Hormones: insulin is a protein.
  • Genes: many genes code for proteins.

Nucleic Acids

  • Major types: DNA and RNA.
  • Found in foods; DNA can be present in organisms you eat.
  • Role: direct cellular activity; genetic information.
  • Monomer: nucleotide (conceptual, not explicitly in the transcript but fundamental).
  • Elements: C, H, O, N, P (CHONP).
  • Structure-function: arrangement of elements/nucleotides determines function; genes code for proteins.