Nucleic acids have a definite polarity, or directionality. stated another way, one end of the molecule is different from the other end. how are these ends described

this protocol provides a detailed procedure for co-immunoprecipitation (co-ip) to identify protein–protein interactions.

organ system-an organ system is a group of organs that work together to perform one or more functions. each does a particular job in the body, and is made up of certain tissues.