Lipids Knowledge-Based Download PDF

Questions

1. 1.

   Which class of lipids consists of a glycerol backbone esterified to two fatty acid chains and a polar, phosphate-containing head group, rendering the molecule amphipathic?

   • A) Triacylglycerols
   • B) Glycerophospholipids
   • C) Sphingolipids
   • D) Waxes
2. 2.

   Which class of lipids consists structurally of an ester formed from a single long-chain fatty acid and a high-molecular-weight monohydric alcohol?

   • A) Triacylglycerols
   • B) Phospholipids
   • C) Waxes
   • D) Sphingolipids
3. 3.

   Which class of lipids is characterized by a core carbon skeleton consisting of four fused rings—three cyclohexane rings and one cyclopentane ring—rather than ester-linked fatty acid chains?

   • A) Triacylglycerols
   • B) Phospholipids
   • C) Waxes
   • D) Steroids
4. 4.

   Which structural characteristic primarily accounts for the significantly lower melting points of naturally occurring unsaturated fatty acids compared to saturated fatty acids of equivalent carbon chain length?

   • A) Formation of intermolecular hydrogen bonding networks between adjacent aliphatic tails
   • B) Adoption of fully extended linear conformations that maximize van der Waals contacts
   • C) Presence of trans-configured double bonds that facilitate dense, ordered crystal packing
   • D) Presence of cis-configured double bonds that produce structural kinks and hinder close molecular packing
5. 5.

   Which alcohol is released along with fatty acid carboxylate salts during the alkaline hydrolysis (saponification) of a triglyceride?

   • A) Ethylene glycol (ethane-1,2-diol)
   • B) Glycerol (propane-1,2,3-triol)
   • C) Cholesterol
   • D) Sphingosine