PCR

Question 1

What is PCR?

Answer 1

Rapid and simple method of copying and amplifying specific DNA sequences

Question 2

How does PCR work?

Answer 2

Consists of repetitive cycles of DNA melting, annealing and synthesis
known sequence of a short region of DNA on each end that needs to be coded and amplified
This is used to design 2 synthetic DNA oligonucleotides, each complementary to the sequence on one strand of the DNA at opposite ends of the region to be amplified
These oligonucleotides serve as primers for in vitro DNA synthesis

Question 3

What are the pros and cons of PCR?

Answer 3

Pros:
- quick
- sample can be frozen
- sensitive
- can be broad or specific
- cheap
Cons:
- sensitive to contamination
- unsure if organisms detected are alive or dead

Question 4

Describe the features of microbial culture

Answer 4

Broad
May require enrichment
Sample needs to be fresh
Detection of live organisms

Question 5

What do PCR and immunodiagnostics (e.g., ELISA) detect?

Answer 5

PCR detects pathogen DNA
Immunodiagnostics detect antibodies against the pathogen