2.2.3 Lipids

• Lipids are soluble in the aqueous environment of cells.

  False
• Fats and oils are composed of glycerol and fatty acids
• What are waxes composed of?

  Long-chain fatty acids and alcohols
• What is the role of phospholipids in cells?

  Form the lipid bilayer
• The diverse structures of lipids allow them to perform structural and functional roles
• Lipids are non-polar molecules.


  True
• The properties of lipids are determined by their hydrophobic nature and solubility characteristics
• Lipids are non-polar molecules that do not interact well with the polar, aqueous environment of cells
• Lipids cannot dissolve in water due to the difference in polarity
• The hydrophobic and non-polar properties of lipids allow them to perform structural and functional roles in cells


  True
• Lipids cannot dissolve in water due to the difference in polarity
• The unique properties of lipids enable them to perform essential structural and functional roles in organisms


  True
• Phospholipids are crucial components of cell membranes
• Fats provide thermal insulation and cushioning for vital organs


  True
• Lipids provide over twice the energy per gram compared to carbohydrates or proteins


  True
• Steroid hormones and eicosanoids act as signaling molecules in cellular communication


  True
• Match the biological role of lipids with its example or function:

  Energy Storage ↔️ Efficient reserves with high energy per gram

  Structural Components ↔️ Phospholipids in cell membranes

  Signaling Molecules ↔️ Steroid hormones regulate development

  Insulation and Protection ↔️ Waxes protect plant leaves from dehydration
• What does it mean for lipids to be hydrophobic?

  They do not interact well with water
• What is the basic structure of lipids?

  Long hydrocarbon chain with polar head group
• Fats are liquid at room temperature.

  False
• Match the type of lipid with its description:

  Fats and Oils ↔️ Solid at room temperature

  Waxes ↔️ Provide a protective coating

  Phospholipids ↔️ Form the lipid bilayer

  Steroids ↔️ Include cholesterol and hormones
• Steroids are composed of four fused hydrocarbon rings.

  True
• What determines the properties of lipids?

  Their molecular structure
• Why are lipids insoluble in water?

  Due to polarity difference
• Lipids lack strong dipoles.


  True
• Lipids lack strong dipoles because they are composed mainly of carbon and hydrogen


  True
• Lipids can dissolve in organic, non-polar solvents like ether and chloroform
• Lipids are non-polar molecules that do not interact well with the polar, aqueous environment of cells
• Lipids can dissolve in organic, non-polar solvents like ether and chloroform
• Lipids store more energy per gram compared to carbohydrates or proteins

  True
• Waxes provide a protective coating on plant and animal surfaces
• Match the function of lipids with its description:

  Energy Storage ↔️ Efficient fuel source, providing over 2x the energy per gram

  Structural Components ↔️ Phospholipids form the lipid bilayer of cell membranes

  Signaling Molecules ↔️ Steroid hormones regulate cellular communication

  Insulation and Protection ↔️ Waxes provide protective coatings on organisms
• Phospholipids form the lipid bilayer of cell membranes
• Lipids play roles in energy storage, structural components, signaling, insulation, and protection in biological systems


  True