17. Biotechnology

Which of the following correctly lists the steps in order for one cycle of the polymerase chain reaction (PCR)?

Why is a DNA polymerase from a thermophilic bacterium used in PCR?

PCR is known for its power of amplifying a target DNA sequence at a high speed. Each cycle can double the number of DNA molecules (target sequence). Which of the following is CORRECT regarding PCR?

If you start with one double-stranded DNA molecule and you perform SIX cycles of PCR, how many double- stranded copies of the DNA will you have?

Suppose you want multiple copies of a gene you have synthesized. How would you obtain the necessary copies by cloning? By PCR?

You have a small gene that you want replicated by PCR. You add fluorescent dye-labeled nucleotides to the PCR thermal cycler. After three replication cycles, what percentage of the DNA single strands will fluoresce?

a. 0%

b. 12.5%

c. 50%

d. 87.5%

e. 100%

In cases of NGU, diagnosis is made using PCR to detect microbial DNA.

a. C. trachomatis

b. E. coli

c. Mycobacterium hominis

d. S. saprophyticus

Indicate which of the following are true and which are false. Rewrite any false statements to make them true by changing the underlined words.

__________ A thermocycler separates molecules based on their size, shape, and electrical charge.

Label the reagents and steps of PCR on the following figure. Indicate the temperature of the reaction at each numbered step.