making a dna profile - lqc 2a Flashcards
1
Q
multi stage process for making a dna profile
A
1) tissue sample obtained and dna extracted
2) dna is cut or goes through PCR to create different sized fragments
3) fragments separated and visualised
4) dna profile compared to a reference profile
2
Q
where can cells be taken for a dna profile
A
cells from cheek swab, white blood cells from blood smear, bone marrow in skeleton, sperm from sexual assault
3
Q
what happens after cells are extracted for dna profile
A
cells are treated with detergent to disrupt their cell membranes and release the dna, proteases are added to inactivate enzymes which could destroy the dna, cold ethanol is added to precipitate out the dna, dna will be amplified if there is a very small sample using a PCR
