Exam 2 Flashcards
most common DNA is early years
semen and white blood cells
telogenic hairs
shed hair, no follicle present
reference sample
choose type of sample and collect under ideal conditions, buccal swab
chain of custody
keeps track of where sample is and who had the sample at all times
mixture
sample containing more than one type of sample, natural
contamination
sample that shouldnt be there due to human error from investigators, accidental
presumptive tests
use antibodies and chemicals to determine sample type, blood versus semen versus saliva
mRNA
messenger RNA that is less stable than DNA
aerosol barrier tips
used on micropiptees to prevent sample from contaminating the pipette and future sampels
nuclease inhibitors
EDTA and Mg++
proteinase K
DTT
chaotropic agents
proteinase k
digests keritan
DTT
breaks di-sulfide bridges
chaotropic agents
reduce h bonds
organic method
origional method, RFLP, need high quantity DNA, yiels dsDNA
denaturing agents in organic method
phenol
chlorophorm
concentrate aqueous in organic method
ethonal precipitation
concentrating column
chelex method
uses chealating resin to remove magnesium, yeilds ssDNA
FTA paper method
stable for years, cannot quantify DNA, static jumping
what do chatoropic agents do
strongly denature
DNA IQ adds
paramegnetic resin to bind DNA
differential extraction works because
sperm doesn’t lyse in absence of reducting agent, remove supernatant
alternatice cell differentiation methods
microfluidic systems
laser dissection
why use Y STR
unfavorable ratio
type pcr inhibitors
heme
indigo
humic acids-soil
melanin
abiological DNA degredation
hydrolitic base removal for ss nick in backbone
light to make thymine dimers
old methods for DNA quantification
spectrometry
gel electrophoresis w/ standards
slot blott
binds DNA to nylon
end point PCR
one locus, all or nothing, measures at end
qPCR
measure every cycle set threshold based on exponential phase
NIST
national institute of standards and technology
mg, mili
10-3
micro
10-6
nano, ng
10-9
pico, pg
10-12
