-Total strands= 2n - strands with exactly same size= 2^n -- 2n -total strands-- same size strands= longer sized strands
Purpose of using both forward and reverse primer?
-primers used for each strand are different, so if only the forward primer were used, only one strand would be replicated -never get product with only the target sequence
2 differences between primers used in
1. in vivo primers are assembled by the enzyme primase, in vitro primers aresynthetically made to match a specific sequence of DNA 2. In vivo primers are initially made of RNA nucleotides and replaced by DNA nucelotides, in vitro primers only use DNA
SYBR green vs. bromophenol blue
SYBR green: binds to negatively charged DNA and glows under short wavelength light, so the DNA bands are visible -Bromophenol blue: just allows us to see how far the sample has migrated, to turn off current
Product in N lane
-cross contamination between lanes -wrong ingredients -bad pipetting
Why test more than one loci?
-you can use hetero/homo to rule things out, but not to say with certainity -you need to test more loci to be certain -2 people might be the same/very similar at any one locus