What Is Life? 2nd Edition by Jay Phelan

Exercise 67

An unsaturated fatty acid is one in which:
A) carbon-carbon double bonds are present in the hydrocarbon chain.
B) the hydrocarbon chain has an odd number of carbons.
C) the hydrocarbon chain has an even number of carbons.
D) no carbon-carbon double bonds are present in the hydrocarbon chain.
E) not all of the carbons in the hydrocarbon chain are bonded to hydrogen atoms.