621. Immunoaffinity chromatography can be used in biochemical applications to
A. break down antibody structure
B. purify protein antigen
C. break down antigen and analyze quantitatively
D. none of the above

622. Different form of a plasmid, on an agarose gel, after electrophoresis may be in which of the following sequence in decreasing molecular weight?
A. Open circular, super coiled, linear plasmid DNA
B. Linear plasmid, open circular, super coiled plasmid
C. Open circular, super coiled, linear plasmid DNA
D. Open circular, linear plasmid, super coiled plasmid

623. In Rocket Immunodiffusion the length of the rocket is
A. proportional to the amount of antibody placed in each well
B. inversely proportional to the amount of antibody placed in each well
C. inversely proportional to the amount of antigen placed in each well
D. proportional to the amount of antigen placed in each well

624. Radial Immunodiffusion is similar to
A. double-diffusion
B. gel diffusion
C. Ouchterloney technique
D. all of these

625. Agarose a porous matrix used in various molecular biology technique is made by repetitive units of
A. maltose
B. agarobiose
C. agar
D. none of these

626. What radioactive molecule is used to end-label an oligonucleotide?
A. (alpha)-32P-ATP
B. (alpha)-32P-dUTP
C. (gamma)-32P-ATP
D. Any of these

627. Which of the following radioactive element is generally involved in RIA?
A. Tritium
B. Carbon-14
C. Iodine-125
D. All of these

628. What is approximatively the half life of 32-Phosphorus?
A. 14 days
B. 28 days
C. 42 days
D. 30 days

629. Rocket Immunodiffusion is also known as
A. gel diffusion
B. electroimmunodiffusion
C. double-diffusion
D. none of these

630. DNA- footprinting is a suitable technique for identifying which of the following?
A. Particular mRNA in mixture
B. Particular t-RNA in mixture
C. Introns within DNA
D. Protein binding site within DNA