LIPIDS

• What are the four primary functions of lipids in living cells?

  Fuel molecules, energy stores, signal molecules, membranes
• What are the types of lipids mentioned in the study material?

  • Phospholipids
  • Sphingolipids
  • Cholesterol
• What is the role of phospholipids in cells?

  Components of membranes
• What are sphingolipids?

  A type of lipid found in membranes
• What is cholesterol's role in cells?

  Component of membranes
• How are lipids classified?

  • Based on their structure and function
  • Types include phospholipids, sphingolipids, cholesterol
• What are fatty acids in relation to lipids?

  Building blocks of lipids
• What are common saturated and unsaturated fatty acids?

  • Saturated: 16:0, 18:0
  • Unsaturated: 18:1(9), 18:2(9,12), 18:3(9,12,15), 20:4(5,8,11,14)
• What is the significance of triacylglycerols?

  They are energy storage lipids
• What are glycerophospholipids?

  • A type of lipid
  • Composed of glycerol, fatty acids, and phosphate groups
• What are sphingosine-derived lipids?

  Include ceramides, cerebrosides, gangliosides, sphingomyelins
• How do sphingosine-derived lipids differ from glycerol-derived lipids?

  Sphingosine has a different backbone structure
• Where are sphingosine-derived lipids primarily found?

  In cell membranes, especially in nerve cells
• What is the core structure of sphingosine-derived lipids?

  3-C core plus long hydrocarbon chain
• What are the biological roles of lipids?

  • Fuel molecules
  • Highly concentrated energy stores
  • Signal molecules
  • Components of membranes
• What are glycerophospholipids?

  Major class of membrane lipids
• What is the backbone structure of sphingosine-derived lipids?

  Sphingosine has a long hydrocarbon chain
• Where are sphingosine-derived lipids primarily found?

  In cell membranes of animal cells
• What is a characteristic of animal sphingosine lipids?

  They can contain sugars, forming glycolipids
• What is the orientation of the sugar moiety in sphingolipids?

  It always faces the extracellular space
• What is the basic structure of steroids?

  Four interconnected carbon rings
• How do steroids function in the body?

  They bind to specific protein receptors
• What is the precursor for terpenes?

  Isopentenyl pyrophosphate
• What are gangliosides?

  Membrane lipids involved in signaling
• What are monoterpenes?

  Aromatic compounds with diverse functions
• How are fatty acids typically structured?

  They have an even number of carbon atoms
• What contributes to the hydrophobic nature of fatty acids?

  Lack of dipoles from C-H and C-C bonds
• What does the systematic name of a fatty acid indicate?

  Number of carbons and degree of unsaturation
• What is a common feature of all lipids?

  They have a hydrophobic fatty acid chain
• What are fatty acids also known as?

  Fats
• What are the major classes of lipids and their functions?

  • Glycerophospholipids: Major membrane components
  • Sphingosine-derived lipids: Cell membrane structure
  • Steroids: Signaling molecules
  • Terpenes: Diverse functions, including aroma
  • Fatty acids: Building blocks of functional lipids
• What are the diverse functions of lipids?

  • Structural: Forming cell membranes
  • Signaling: Hormonal functions (steroids)
  • Enzyme cofactors: Vitamins
  • Energy storage: Long-term energy reserves
• What is the common structural feature of all lipids?

  • Hydrophobic fatty acid chains
  • Can be linear or ring structures
  • Composed mainly of carbon and hydrogen
• How are fatty acids assembled into functional lipids?

  • Linked to glycerol backbone in phospholipids
  • Complexed with other molecules based on function
  • Formed into various structures depending on needs
• What is the final form of fatty acids in molecules?

  They exist in various forms in molecules
• How are fatty acids linked in phospholipids?

  A glycerol backbone links two fatty acids and one phosphate
• Do fatty acids generally exist free in vivo?

  No, they are complexed to other molecules
• What is the composition of a fatty acid chain?

  It is composed of an even number of carbon atoms
• Why are fatty acids hydrophobic?

  Due to the lack of dipoles from C-H and C-C bonds
• Which elements are not very electronegative in fatty acids?

  Carbon and hydrogen