B1.1 Carbohydrates and Lipids Notes

B1.1 Carbohydrates and Lipids

B1.1.1: Chemical Properties of Carbon

  • Carbon atoms can form up to four covalent bonds, allowing for diverse compounds.
  • Diversity includes branched/unbranched chains and single/multiple rings.

B1.1.2: Macromolecule Production

  • Macromolecules are produced via condensation reactions, linking monomers to form polymers.

B1.1.3: Polymer Digestion

  • Polymers are digested into monomers through hydrolysis reactions.

B1.1.4: Monosaccharides

  • Monosaccharides include pentoses (5-carbon) and hexoses (6-carbon).
  • Glucose is soluble, transportable, chemically stable, and yields energy upon oxidation.

B1.1.5: Polysaccharides

  • Polysaccharides (starch, glycogen) serve as energy storage compounds.
  • Compact due to coiling and branching; relatively insoluble. Easily adding/removing alpha-glucose monomers

B1.1.6: Cellulose

  • Cellulose's structure is related to its function in plant cell walls.
  • Beta-glucose monomers alternate orientation, forming straight chains grouped in bundles and cross-linked with hydrogen bonds.

B1.1.7: Glycoproteins

  • Glycoproteins are involved in cell-cell recognition.
  • Act as antigens (e.g., ABO blood groups).

B1.1.8: Lipids

  • Lipids are hydrophobic substances, including fats, oils, waxes, and steroids.

B1.1.9: Triglycerides and Phospholipids

  • Triglycerides and phospholipids are formed by condensation reactions.
  • One glycerol molecule can link three fatty acid molecules (triglycerides) or two fatty acid molecules and one phosphate group (phospholipids).

B1.1.10: Fatty Acids

  • Saturated fatty acids have no double bonds; unsaturated fatty acids have one or more double bonds.
  • Monounsaturated have one double bond, polyunsaturated have multiple.

B1.1.11: Triglycerides

  • Triglycerides in adipose tissues for energy storage and thermal insulation.

B1.1.12: Phospholipid Bilayers

  • Phospholipid bilayers form due to hydrophobic and hydrophilic regions (amphipathic).

B1.1.13: Steroids

  • Non-polar steroids can pass through the phospholipid bilayer.

Key Terms

  • SI Units: International System of Units, prefixes like kilo-, centi-, milli-, micro-, nano-.
  • Monomers: Glucose, amino acids, nucleotides, fatty acids and glycerol
  • Polymers: Polysaccharides, polypeptides, polynucleotides, triglycerides.
  • Carbohydrates: Sugars, starch, cellulose
  • Lipids: Fats, oils, waxes, steroids.
  • Reactions: Condensation, hydrolysis.
  • Cellulose Microfibrils: bundles held together by hydrogen bonds
  • Steroids: Lipids with four carbon rings (e.g., cholesterol, oestradiol, testosterone)