Application:
• Lipids are more suitable for long-term energy storage in humans than carbohydrates
Lipids and carbohydrates both function as energy storage molecules in humans, however differ in several key aspects:
- Storage (lipids are more suitable for long-term energy storage)
- Osmolality (lipids have less of an effect on the osmotic pressure of a cell)
- Digestion (carbohydrates are easier to digest and utilise)
- ATP Yield (lipids store more energy per gram)
- Solubility (carbohydrates are easier to transport in the bloodstream)
Mnemonic: SODAS
Energy Storage Comparison (Carbohydrates vs Lipids)
Energy Storage Analogy
ATP is the energy currency of the cell – in this respect it is akin to cash
- Cash is earned when you work (cell respiration) and can be spent in a number of ways (metabolism)
Storing energy as carbohydrates (i.e. glycogen) is similar to keeping the cash in a wallet
- It is easier to carry around (monosaccharides and disaccharides are water soluble)
- It is readily accessible (carbohydrates are easier to digest)
- You cannot carry as much (carbohydrates store less energy per gram)
Storing energy as lipids (i.e. triglycerides) is similar to keeping the cash in a safe
- It is not viable to carry around (triglycerides are insoluble in water)
- It is harder to access (triglycerides cannot be easily digested)
- You can keep more cash in it (triglycerides store more energy per gram)
Energy Storage Analogy (Carbohydrates vs Lipids)
