Cell membranes are primarily made of a component that contains fatty acids. This component is most likely a... a. carbohydrate.
b. protein.
c. nucleic acid.
d. lipid.

d. lipid.

Explanation:

The lipid bilayer acts as a barrier to the passage of molecules and ions into and out of the cell

c.) polymerase chain reaction

- "unlike the original dna fingerprinting method, dna profiling does not use restriction enzymes to cut the dna. instead it uses the polymerase chain reaction (pcr)? to produce many copies of specific str sequences. pcr is an automated procedure that generates lots of copies of a specific sequence of dna."