Question

Saturated fatty acids are different to unsaturated fatty acids because they ________. Have no C=C double bonds Have short hydrophobic tails Exhibit free rotation about the carbon-carbon bonds in the hydrocarbon tail Have an even number of carbon atoms

Answer 1

Have no C=C double bonds

Step-by-step explanation:

An saturated compound is the one that cannot undergo certain addition reactions like a hydrogenation, which means that they do not have any double or triple bonds. Therefore Unsaturated Fatty acids do have double bonds, they can be monounsaturated (with one C=C bond) like oleic acid, or polyunsaturated (many C=C bonds) like DHA with 6 unsaturations.

Saturated or unsaturated fatty acids can have short or long hydrophobic tail and both categories can have an even number of carbon atoms:

with 14 C : Myristoleic acid (unsaturated) - Myristic acid (saturated)

with 22 C : DHA (unsaturated) - Behenic acid (saturated)

Any single bond C-C can have free rotation, and even though unsaturated fatty acids presents double bonds they also have single bonds in their hydrocarbon tail.