Polymerase Chain Reaction is not used in :

1. Confirming presence of a pathogen during early infection

2. Identifying the mutated genes in suspected cancer patients

3. Isolating the gene of interest from host DNA to be cloned by recombinant procedures

4. Detection of the presence of HIV in suspected AIDS patient

A single strand of nucleic acid tagged with a radioactive molecule is called

1. vector

2. selectable marker

3. plasmid

4. probe

DNA or RNA segment tagged with a radioactive molecule is called

1. vector

2. probe

3. clone

4. plasmid

For effective treatment of a disease: 

(1) Early diagnosis is needed but understanding of its pathophysiology is not needed

(2) Early diagnosis is not needed but understanding of its pathophysiology is needed

(3) Early diagnosis and understanding of its pathophysiology are needed

(4) Neither early diagnosis nor understanding of its pathophysiology is needed

Probes are molecules of