MI 1.1.3 & 1.1.5 Assessment Questions

Which of the following is/are NOT required to perform successful cycle sequencing of pathogenic DNA?

• heat resistant DNA polymerase

• free nucleotides

• free fluorescent dideoxynucleotides

• thermocycler device

• primers designed to target specifically human DNA

Place the following steps of cycle sequencing unknown pathogenic DNA in order.

1. Polymerase chain reaction using fluorescent ddNTPs

2. Laser excitation and interpretation of the resulting chromatogram

3. Denature the sample DNA

4. Gel electrophoresis separates the newly formed DNA fragments by length

5. Isolate the pathogenic DNA using specific primers

• 3, 5, 1, 4, 2

• 3, 5, 4, 2, 1

• 3, 2, 1, 5, 4

• 1, 5, 4, 2, 3

In DNA cycle sequencing, what occurs when a dideoxynucleotide (ddNTP) is added to the growing end of a nucleic acid polymer?

• the next nucleotide can attach (elongation)

• the primer can attach

• the elongation phase ends (polymer termination)

• a chromatogram is analyzed

During ELISA, the secondary antibody is linked to an enzyme. Identify the appropriate response when the substrate to the enzyme is added.

• The substrate binds to the primary antibody causing a color change.

• The substrate binds to the enzyme and destroys the antigen, resulting in a color change.

• The substrate binds to the enzyme causing a chemical reaction that leads to a color change.

• The substrate binds directly to the antigen causing a color change.

Which of the following cannot be determined by ELISA?

• Concentration of antigen

• Presence of disease (antigen)

• Genetic sequence of a pathogen

• Presence of specific hormones

After adding the enzyme-linked secondary antibody to the ELISA and washing off the unbound antibody, what is added to the assay in order to determine the presence or absence of disease antigen?

• enzyme substrate

• primary antibody

• DNA polymerase

• new patient sample