Lipid Classification Flashcards
What is the structure of a fatty acid?
Hydrophobic: hydrocarbon chains
Hydrophilic: terminal carboxyl group with pKa of ~4.8
What is a saturated fatty acid?
Saturated fatty acids: no double bonds (carbons havea maximal single bonds)
What is a mono or polyunsaturated fatty acid?
Unsaturated fatty acids: carbons have 1 or more double bonds (mono-‐ or polyunsaturated)
What are characteristics of double bonds?
In unsaturated fatty acids, the double bonds are in the cis conformation (NOT trans). The double bonds cause the fatty acids to bend and have “kinks”. The double bonds are spaced in 3-carbon intervals.
How do double bonds effect melting temperature (Tm) and fluidity?
Increasing the number of double bonds (unsaturation) reduces the Tm and increases fluidity
How does increasing chain length effect the melting temperature and fluidity?
Increasing the chain length increases melting temperature and decreases fluidity.
What are the two essential fatty acids?
We have to get fatty acids from our diet! The two essential fatty acids are linoleic acid (omega 6) and alpha-linolenic acid (omega 3). They are 2 fatty acids plants provide and humans cannot make.
Why are essential fatty acids “essential”?
These fatty acids are essential because linoleic acid is a precursor for other shorter omega 6 fatty acids. Alpha-linolenic acid is a precursor for omega-3 fatty acids: important for growth and development.
What fatty acids can become “essential” if linoleic acid is unavailable?
Arachidonic acid can become an essential fatty acid of linoleic acid is deficient in the diet. It is a substrate for prostaglandin synthesis.
