A polymerase chain reaction (PCR) was set up with the following reagents: DNA template, Taq polymerase, buffer, dNTPs, and Mg²⁺. Which one of the following is missing in the reaction mixture?

Expression of hundreds of different genes in DNA microarray technology is monitored by using

A. Radioactive probe

B. Visible chromogenic probe

C. UV absorbing probe

D. Fluorescent probe

Identical sized RNA transcript is detected by Northern blot analysis of UDP glucuronosyl transferase obtained from human liver and kidney. Microarray analysis of the same samples shows equal spot intensity, whereas Western blot detects a 55 kDa strong band in liver, but a very faint in kidney of same size. The regulation of UDP glucuronosyl transferase is

A. Transcriptionally controlled

B. Post-transcriptionally controlled

C. Translationally controlled

D. Post-translationally controlled

Which one of the following techniques/tools is not used for inserting a foreign gene into a cell?

A. DNA microarray

B. Electroporation

C. Gene gun

D. Microinjection

Which one of the following techniques can be used to compare the expression of a large number of genes in two biological samples in a single experiment?

A. Polymerase chain reaction

B. DNA microarray

C. Northern hybridization

D. Southern hybridization