FORENSIC DNA APPLICATIONS
1Ques-Why do we add 1* lysis buffer and Proteinase K to the sample ?
Ans- Lysis buffer is used for the purpose of breaking open cell to isolate
the DNA from the sample whereas Proteinase K is used to digest many
contaminated proteins present in the sample. It also protects the DNA
from nuclease attack.
2Ques-Why do we add 5M NaCl to each sample?
Ans- NaCl is used to stabilize the DNA after its separation from the
protein and aid in precipitations.
3Ques-Define the term Pellet and Supernatant.
Ans- Pellet-A small compressed mass of a substance is known as pellet.
Supernatant-Liquid which is left over the solid residue after centrifugation
is known as supernatant.
4Ques- List the two important checks needed prior to use of a centrifuge
Ans- 1.The work of centrifuge must be levelled.
2. Balance the tubes in the rotor.
5Ques-In step 20, why do we add ethanol to the sample?
Ans- After Centrifugation ethanol is added in the sample because
ethanol causes DNA protein to come out of the solution. Moreover DNA
is insoluble in ethanol and helps in formation of white precipitations.
1Ques-Why do we add 1* lysis buffer and Proteinase K to the sample ?
Ans- Lysis buffer is used for the purpose of breaking open cell to isolate
the DNA from the sample whereas Proteinase K is used to digest many
contaminated proteins present in the sample. It also protects the DNA
from nuclease attack.
2Ques-Why do we add 5M NaCl to each sample?
Ans- NaCl is used to stabilize the DNA after its separation from the
protein and aid in precipitations.
3Ques-Define the term Pellet and Supernatant.
Ans- Pellet-A small compressed mass of a substance is known as pellet.
Supernatant-Liquid which is left over the solid residue after centrifugation
is known as supernatant.
4Ques- List the two important checks needed prior to use of a centrifuge
Ans- 1.The work of centrifuge must be levelled.
2. Balance the tubes in the rotor.
5Ques-In step 20, why do we add ethanol to the sample?
Ans- After Centrifugation ethanol is added in the sample because
ethanol causes DNA protein to come out of the solution. Moreover DNA
is insoluble in ethanol and helps in formation of white precipitations.
