Lipids Flashcards
Describe the structure and properties of glycerol and fatty acids (in lipids).
Glycerol:
- Molecular formula C3H8O3. Three-carbon alcohol, with each carbon bearing a hydroxyl (OH) group.
- Soluble in water because of its polar -OH group.
Fatty acids:
- Carboxylic acids (An acidic hydrophilic carboxyl (COOH) functional group at one end & an attached hydrophobic hydrocarbon chain)
- Possess long carbon skeletons (between 12-20 carbons). Each carbon joins to hydrogen atoms.
- Fats are hydrophobic due to abundance of non-polar C-H bonds.
Describe the formation and breakage of ester bonds.
Formation: Condensation reaction where small molecules are combined to form larger molecules with the formation of water molecule
Breakage: Hydrolysis reaction where large molecules are broken into smaller molecules with the addition of water.
Describe the structures and properties of triglyceride. Explain how these are related to its roles in living organism.
- Higher proportion of C and H atoms compared to O atoms. (Triglycerides contain a greater number of carbon atoms per unit mass than carbohydrates)
- More efficient energy stores than carbohydrates, releases a larger amount of energy. (1g of fat releases 38kJ/g of energy, 1g of carbohydrates releases 17kJ/g of energy) - Highly reduced molecules