USMLE

Steroids

724 views
Lipids
  1. Fatty Acids
  2. Triacylglycerols
  3. Phospholipids
  4. Sphingolipids
  5. Terpenes
  6. Steroids
  7. Waxes

Summary

Coming soon...

Key Points

  • Steroids
    • Structure:
      • 4-ringed structures 
        • Some have short tail
        • Steroids with OH group attached are called sterols
      • Formed from squalene
        • Compare to how TAG = made from fatty acids?
        • Squalene is most common terpene (reference terpenes pathway)
    • Roles: 
      • Cholesterol is most common steroid
        • Maintains membrane stability and fluidity
        • Cholesterol is precursor to:
          • Steroid Hormones
            • Lipids are useful as precursors for signaling molecules like hormones because they can pass through cellular membranes
            • Synthesized in liver
          • Vitamin D
            • Fat-soluble vitamin
            • Cannot be produced by the body
            • Transported with dietary fats to help absorption  
    • Nonpolar/hydrophobic