The MacBook Pro follows, with its prices going from $2,199 down to $1,999 for the 15-inch version (and from $1,499 for the 13-inch version down to $1,299). That's a break from traditional Apple pricing, where prices would remain the same generation over generation, with updated components adding value.
Restriction enzymes can also be used to generate compatible ends on PCR products. In all cases, one or more restriction enzymes are used to digest the DNA resulting in either non-directional or directional insertion into the compatible plasmid.
PCR (polymerase chain reaction): PCR (polymerase chain reaction) is a technique in molecular genetics that permits the analysis of any short sequence of DNA (or RNA) even in samples containing only minute quantities of DNA or RNA. PCR is used to reproduce (amplify) selected sections of DNA or RNA for analysis. Previously, amplification of DNA involved cloning the segments of interest into vectors for expression in bacteria, and took weeks. But now, with PCR done in test tubes, it takes only a few hours.