17735793
Description
Mind Map by Anele Yonela Ngcebetsha , updated more than 1 year ago
More
1.5 Lipids
- TRIGLYCERIDES
- Three (tri) Fatty Acids
- Glycerol (glyceride)
- Each fatty acid forms an ESTER bond with glycerol in a CONDENSATION REACTION
- Glycerol molecule is same in all moleculets but there are variations in the fatty acids meaning there are different properties
- Saturated = NO carbon-carbon double bonds
- Mono-unsaturated = 1 double bond
- Polyunsaturated = More than 1 Double bond
- Saturated = NO carbon-carbon double bonds
- High ratio of energy-storing Carbon-hydrogen bonds to carbon atoms = excellent source of energy
- Low mass to energy ratio = good storage molecules. Beneficial to animals as reduced mass to carry around
- Large, non-polar and insoluble = doesn't effect osmosis in cells or water potential in them
- Triglycerides release water when oxidised, meaning they're an important source of water for organisms, especially those living in dry conditions
- Three (tri) Fatty Acids
- PHOSPHOLIPIDS
- Similar to triglycerides but one fatty acid replaced with a PHOSPHATE MOLECULE
- Fatty acid molecules - Hydrophobic 'tail'
- Phosphate Molecules - Hydrophillic 'head'
- Phosphate Molecules - Hydrophillic 'head'
- Polar
- Properties
- Polar so form a bilayer between intercellular and extra cellular
- Phospholipid structure allows them to form glycolipids by combining with carbohydrates within the cell-surface membrane. These glycolipids are important in cell recognition
- Polar so form a bilayer between intercellular and extra cellular
- Similar to triglycerides but one fatty acid replaced with a PHOSPHATE MOLECULE
- Characteristics
- Contain: Carbon, Oxygen and Hydrogen
- Proportion of oxygen to carbon and hydrogen is smaller than in carbohydrates
- Soluble in solvents such as alcohols and acetone
- Insoluble in water
- Contain: Carbon, Oxygen and Hydrogen
- Roles of Lipids
- Source of Energy
- When oxidised, lipids provide over 2x the energy of carbohydrates
- When oxidised, lipids provide over 2x the energy of carbohydrates
- Waterproofing
- Lipids are insoluble = good at waterproofing.
- Both plants and insects have waxy, lipid cuticles that conserve water. Where as mammals produce an oily secretion from the sebaceous glands in the skin
- Both plants and insects have waxy, lipid cuticles that conserve water. Where as mammals produce an oily secretion from the sebaceous glands in the skin
- Lipids are insoluble = good at waterproofing.
- Insulation
- Fats are slow conductors of heat meaning when stored they help retain body heat. They also act as electrical insulators in the myelin sheath around nerve cells
- Fats are slow conductors of heat meaning when stored they help retain body heat. They also act as electrical insulators in the myelin sheath around nerve cells
- Protection
- Fat is often stored around delicate organs
- Fat is often stored around delicate organs
- Source of Energy
- Testing For Lipids
- Dry and grease-free testube
- Add sample and ethanol
- Shake tube throughly and dissolve lipid in sample
- Add water, shake gently
- Cloudy white = lipid present and emulsion formed
- As a control, repeat the procedures using after instead of the sample; the final solution should be clear
- As a control, repeat the procedures using after instead of the sample; the final solution should be clear
- Cloudy white = lipid present and emulsion formed
- Add water, shake gently
- Shake tube throughly and dissolve lipid in sample
- Add sample and ethanol
- Dry and grease-free testube
Media attachments
Want to create your own Mind Maps for free with GoConqr? Learn more.