Ch.9 Flashcards
What type of DNA can be used to identify related people in humans?
mitochondrial DNA (mtDNA), which is inherited only from the mother
What are restriction enzymes used for?
- cut DNA strands in at a recognition sequence
- Generates restriction fragments
-Complementary “sticky” ends can anneal with one another - DNA ligase joins molecules covalently
- Allows creation of recombinant DNA molecules
What enzyme is used to generate cDNA from pre-mRNA?
Reverse Transcriptase
What are 2 common vectors used for cloning genes?
Plasmids and bacteriophages
What is a DNA library used for?
collection of clones that together contain the entire genome of an organism
What are the goals of gene cloning?
- to create multiple identical copies of a specific gene of interest
- Protein production
- DNA production
- Research tools
In CRISPR Cas9, how does Cas9 nuclease cut?
use a piece of single-stranded RNA (gRNA) as a guide to make a double-stranded cut at a precise location in the DNA
What is PCR used for?
- Allows creation of over a billion copies of a given region of DNA in hours
- Allows detection of specific sequences
- Can detect pathogens without culturing
What is Taq polymerase?
heat-stable (does not denature) DNA polymerase from Thermus aquaticus
Does PCR produce fragments of different sizes or fragments of the same size? How?
- PCR produces fragments of the same size
- two primers used in PCR target DNA to amplify
- To amplify a DNA sequence encoding a specific protein, the nucleotide sequences at the ends of the gene must be known
How does the DNA microarray work?
(gene chip) tens to thousands of DNA spots are placed on a glass slide or other solid support
- Each spot contains many copies of a specific oligonucleotide (short DNA sequence) which functions like a probe
- Used to study gene expression in organisms whose genomes have been sequenced
What are DNA probes used for? How are they obtained? How are they tagged?
- DNA probes locate specific nucleotide sequence
- Probe is single-stranded piece of DNA, complementary to sequence of interest, labelled with a marker
- DNA probes are obtained by synthesizing a known DNA sequence of interest
- DNA probes are tagged with fluorscence
Why is the concern that genetically modified foods contain DNA an unfounded one?
- Genetically modified (GM) organisms hold promise
- Concerns over possible allergens
- Unintended effects on environment
What are reasonable concerns regarding biotechnology?
- Creation of new infectious agents for bioterrorism
- Concerns over possible allergens
- Unintended effects on environment
