What are restriction enzymes and where do they come from?
They are enzymes used for cutting out specific sections of DNA
They evolved in bacteria as defense mechanisms against viruses.
Why can’t you use water as a buffer for electrophoresis?
Buffer solutions contain salts, which help conduct electricity.
What are the 3 things electrophoresis separates molecules based on?
Mass
Shape
Charge
What is CRISPR-Cas9 and how is it used in genetics?
CRISPR-Cas9 is a method of editing DNA by “programming” enzymes to find a particular DNA sequence in a host cell and cut it out.
It can be used in gene therapy or food and livestock modification.
What is a restriction site?
A restriction site is a section on a DNA strand that enzymes bind to.
What charge is DNA and how do you know?
Negative
The phosphate groups make them negative.
What is a DNA ladder and why is it used?
A DNA ladder is a set of DNA fragments that’s as a comparison between altered and unaltered DNA.
DNA ladders identify weight, size, and stability of DNA fragments
What are 2 reasons why we add loading dye to a DNA sample?
Makes the sample visible
The dye contains glycerin which adds density to the sample, allowing it to move quickly.
What is lambda and why significance does it have to biology?
Lambda is a virus. Its DNA is used as a standard for comparison in molecular biology to stabilize DNA fragments.
What is a plasmid? What are the shapes?
Circular DNA found in bacteria.
What did NEBcutter allow you to do this lab activity?
NEBcutter allowed you to determine which enzyme would be best for cutting a particular section of DNA
Who was the scientist that developed DNA fingerprinting and what in what year?
Dr. Allen Jefferys
1986
Who was the actual rapist and murder in Narborough, England?
Collin Pitchfork
Who was falsely accused of raping and killing the two women in the foot path murders?
Richard Buckland
Who wrote a book over the foot path murders?
Joseph Wambaugh
Who were the two victims in the footpath murders?
Lynda Mann & Dawn Ashworth
When placing DNA in an electrophoresis chamber, which side (anode or cathode) should the wells be placed near?
Cathode, the negative end, because DNA is negative and will travel to the anode, positive.
Which laboratory tool would allow you to do a paternity test?
Electrophoresis
What gel is used to separate DNA or RNA molecules?
Agarose
A virus that infects and replicates inside bacteria.
Bacteriophage
DNA molecules that are linked together like chains after replication.
Catenates
The transfer of DNA between two bacterial cells through direct contact.
Conjugation
Describes circular DNA that has a single-strand break (one side cut).
Nicked
A small, circular piece of DNA found in bacteria that can replicate independently
Plasmid
A tube-like structure that connects bacterial cells during conjugation to transfer DNA.
Sex Pilus
DNA that is tightly twisted, making it compact.
Supercoiled
A gel-like substance used to separate DNA fragments by size.
Agarose
The positive end of an electrical field where negatively charged DNA moves toward.
Anode
Visible lines showing DNA fragments of different sizes after electrophoresis.
Bands (on a gel)
The negative end of an electrical field; DNA starts near this end because it’s negatively charged.
Cathode
A tool used to create wells in the gel for loading DNA samples.
Comb
A pattern of DNA bands unique to each person, used for identification.
DNA Fingerprint
A mixture of DNA fragments of known sizes used as a reference in a gel.
DNA Ladder
A liquid solution that carries electric current through the gel.
Electrophoresis Buffer
The use of scientific methods to solve crimes or identify individuals.
Forensics
A type of bacteriophage often used as a source of DNA in lab experiments.
Lambda
The separate columns in the gel where each DNA sample is loaded.
Lanes (on a gel)
A colored solution added to DNA samples to help see and track them during electrophoresis.
Loading/Tracking Dye
Small holes in the gel where DNA samples are placed before running the gel.
Wells (in a gel)
The matching units of DNA: A–T and G–C.
Base Pairs
DNA ends that are cut straight across, with no overhangs.
Blunt Ends
A gene-editing tool that can precisely cut and modify DNA sequences.
CRISPR-Cas9
An enzyme that cuts DNA at specific sequences.
Endonuclease (Restriction Enzyme)
The exact DNA sequence where a restriction enzyme cuts.
Restriction Site
DNA ends that have short single-stranded overhangs after being cut by enzymes, allowing them to join easily with matching ends.
Sticky Ends