lipids

• What are the main elements that lipids contain?


  Carbon, hydrogen, and oxygen
• How are fats and oils differentiated based on their state at room temperature?


  Fats are solid, while oils are liquid at room temperature
• Why are lipids considered non-polar molecules?


  Because the electrons in their outer orbitals are evenly distributed
• What is the significance of lipids being non-soluble in water?


  It means that oil and water do not mix
• What are lipids classified as in terms of molecular size?

  Macromolecules
• What are the two main types of lipids discussed in the material?

  Triglycerides and phospholipids
• What is a triglyceride composed of?


  One glycerol molecule and three fatty acids
• What group of molecules does glycerol belong to?


  Alcohols
• What is the structure of fatty acids?


  They consist of a carbonyl group (-COOH) with a hydrocarbon chain
• What is the process called when triglycerides are formed?

  Esterification
• What type of reaction occurs when triglycerides are broken down?


  Hydrolysis reaction
• What are saturated fatty acids characterized by?


  No double bonds between carbon atoms
• How are unsaturated fatty acids defined?


  They contain one or more double bonds between carbon atoms
• What effect do double bonds have on fatty acid structure?


  They cause the molecule to kink or bend
• Why are unsaturated triglycerides typically liquid at room temperature?


  Because their structure prevents them from packing closely together
• What health implications are associated with saturated fats?


  They may lead to coronary heart disease
• What are phospholipids modified from?


  Triglycerides
• What additional element do phospholipids contain compared to triglycerides?


  Phosphorus
• What is the charge of inorganic phosphate ions?


  Negatively charged
• How do phospholipids behave when interacting with water?


  They form a layer with phosphate heads in water and fatty acid tails out
• What is a bilayer formation in phospholipids?


  It is a two-layered sheet with hydrophobic tails pointing inward
• What role do phospholipids play in cell membranes?


  They separate the aqueous environment from the cytosol
• What are sterols also known as?


  Steroid alcohols
• What is the basic structure of sterols?


  A four carbon ring structure with a hydroxyl group
• What is the role of cholesterol in cell membranes?


  It adds stability and regulates fluidity
• Where is cholesterol primarily manufactured in the body?


  In the liver and intestines
• What are some products manufactured using cholesterol?


  Vitamin D, steroid hormones, and bile
• What are the biological roles of lipids?


  • Membrane formation and hydrophobic barriers
  • Hormone production
  • Electrical insulation for impulse transmission
  • Waterproofing (e.g., in birds' feathers)
  • Long-term energy storage
  • Thermal insulation
  • Cushioning for vital organs
  • Buoyancy for aquatic animals
• How can lipids be identified in the laboratory?


  By using the emulsion test
• What is the procedure for the emulsion test for lipids?


  Mix the sample with ethanol, then with water, and shake
• What indicates the presence of a lipid in the emulsion test?


  A white emulsion forming as a layer on top of the solution
• What is food synergy?


  • The combined effect of a range of nutrients
  • Whole grains having a greater effect than individual components
  • The interaction of various foods to enhance health benefits
• What is the relationship between the structure of fatty acids and their state at room temperature?


  Oils are liquid due to unsaturated fatty acids, while fats are solid due to saturated fatty acids
• How do the properties of vegetable oils differ from animal fats?

  Vegetable oils are more liquid than animal fats
• What is the significance of hydrogenated fats in spreads?


  They are linked to health issues and are being reduced in many spreads
• How do different degrees of lipids release energy?


  They release the same quantity of energy gram for gram
• What are the similarities and differences between saturated and unsaturated fats?


  Similarities:

  • Both are types of lipids
  • Both provide energy

  
  

  Differences:

  • Saturated fats have no double bonds; unsaturated fats have one or more double bonds
  • Saturated fats are solid at room temperature; unsaturated fats are liquid