Lipids are a broad group of biomolecules containing an assortment of structurally diverse types. What makes a biomolecule a lipid is its solubility in organic solvents, so lipids invariably have large portions of their structure with only carbons and hydrogens, though many important lipids are amphiphilic. An amphiphile is a chemical compound possessing both hydrophilic and hydrophobic moeities properties.
It helps in categorizing biological lipids to see that they fall into two categories based on biosynthesis, in that they originate entirely or in part from two distinct types of biochemical subunits or building-blocks: ketoacyl and isoprene groups. Although the biosynthesis of macromolecular precursors as a general topic is one step past the 1st semester biochem approach in the new MCAT, knowing a little bit about lipid biosynthesis is recommended because a little bit goes a long way in making lipids more coherent. Important classes of lipids include fatty acids, glycerolipids, glycerophospholipids, sphingolipids, polyketides, sterol lipids and prenol lipids.
Conceptual Vocabulary Self-Test
Basic Terms Crossword Puzzle
Basic Puzzle Solution
Conceptual Vocabulary for Lipids