DNA Basics
PCR
DNA Extraction
Analyzing Fingerprints
Gel electrophoresis
100

What does DNA stand for?

Deoxyribonucleic Acid

100

What does the polymerase chain reaction do?

It makes copies of an original DNA template.

100

Where is DNA extracted from? 

The nucleus of cell

100

 DNA evidence is collected from the scene of a burglary. Which of the three suspects most likely committed the crime?

Suspect 2 most likely did it because this suspect's DNA matches the crime scene DNA.

100

What is a restriction enzyme

A restriction enzyme is an enzyme that cuts DNA at a specific 6-8 nucleotide sequence.

200

What is the shape or structure of DNA?

Double helix (or spiral staircase, twisted ladder)

200

How does PCR help forensic scientists collecting DNA from a crime scene?

PCR can make copies of the DNA found in a crime scene sample, even if it contains very small amounts of DNA.

200

Give examples of cells that don't contain DNA.

Cells without a nucleus example Hair, blood, etc

200

Suspect C probably committed the crime because this suspect's DNA matches the crime scene.

200

How can restriction enzymes be used to distinguish between 2 peoples DNA? 

Restriction enzymes will cut two different people's DNA in different places, causing a different band pattern when the samples are run on a gel.

300

What are the four chemical letters of DNA?

Adenine (A), Thymine (T), Cytosine (C), and Guanine (G) A, T, C, G

300

What happens during the denaturation step of PCR?

The sample is heated to 95° C, causing the two strands of DNA to separate into single strands.

300

What chemicals are used to break open the cell and unwind the DNA? 

Salt and meat tenderizor.  

300

 A murder victim was found and was in an apparent struggle with the murderer. A bit of skin was found underneath the victim's fingernails and sent out for DNA fingerprinting. Which of the suspects most likely committed the crime?

 Suspect 1 is a match for the specimen found under the victim's fingernails so most likely committed the murder.

300

How can you tell if a gel is running

Look for bubbles

400

How do the nucleotides, or chemical letters, of DNA, pair up with each other?

A pairs with T C pairs with G

400

What happens during the annealing step of PCR?

The sample is cooled to around 50-60° C, allowing short DNA primers to bind to certain sequences of the DNA template.

400
What is the purpose of the salt?
To clump proteins together 
400

 Which of these men is most likely the father of the baby?

 Dad 3. Only Dad 3 has all of the bands that the child did not inherit from the mother.

400

What charge is DNA? 

negative

500

What 3 molecules make up a nucleotide

Sugar (deoxyribose), phosphate, and a Base (A,G,T,C)

500

What happens during the extension step of PCR?

The sample is heated to 72° C, allowing DNA polymerase to copy the DNA around the primers.

500

List all chemicals involved in DNA extraction and their proper order

Soap, enzyme, salt, alcohol 

Soap used to break open cell membranes, enzyme used to unwind DNA, salt used to clump up proteins, and alcohol used to make DNA visible.

500
Which of these sets of twins are identical?
The B and C sets of twins are identical. The A and D sets of twins are fraternal.
500

What is the purpose of gel Electrophoresis?

To make DNA visible in a DNA fingerprint?