CATALYST (11.12.2008)
Take out your quiz from Monday and trade with
the person sitting in front of you. If you are in
the front row, take your paper to the back of the
classroom.
 Begin working on your quiz, you have 15 minutes
to complete it.
 Once you have completed your quiz return it to
the creator to be graded.
 Turn in all graded quizes.

CATALYST (11.13.2008)
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“The aim of this research [at the University of Leicester] is
to understand how potential jurors perceive and
understand various forensic science techniques, in order to
determine how their attitudes and expectations may
impact on their decision making in a courtroom setting.”
“Forensic science is featured quite heavily in television
programming and news media coverage, and this raises the
public interest in forensic techniques. An important aspect
of jury decision making is a juror's prior beliefs and
knowledge, and this study aims to investigate how
potential jurors' perceptions of forensic science impacts on
their ability to evaluate different types of evidence.”
How do you think shows like CSI affect a
juror’s ability to make judgments in a case?
DNA FINGERPRINTING
SIMULATION
LAB 7.3: OBJECTIVES
Assume the role of a forensic scientist in an
attempt to solve a violent crime using DNA
evidence.
 Employ agarose electrophoresis to separate
digested DNA fragments according to size.
 Identify the guilty suspect based on the DNA
fingerprinting evidence.
 Understand the principles and practices of DNA
technology as applied to the forensic sciences.
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LAB 7.3: SCENARIO
Police were called to the scene of a homicide.
Found at the scene was a large amount of blood.
Blood typing revealed that not only was the blood
of the victim present at the scene, but also blood
from another person, assumed to be the guilty
party.
 Blood evidence was collected at the scene. Blood
samples from four suspects were also drawn
under court order and all samples were found to
be of the same blood type as the blood believed to
have come from the perpetrator of the crime.
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LAB 7.3: SCENARIO
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The police have turned to you and your fellow lab
technicians to employ the process of DNA
fingerprinting in building a case against one of
the suspects.
LAB 7.3: PRE-LAB QUESTIONS
1.
2.
3.
4.
5.
6.
Summarize the scenario in one sentence.
Why were the police unable to use blood type to
identify the perpetrator?
What type of DNA will be analyzed on the gel?
What is electrophoresis? What property does
DNA posses that allows us to visualize banding
patterns using electrophoresis?
How do we get enough DNA from blood samples
to analyze using gel electrophoresis?
What safety precautions should be taken before
beginning this lab?
LAB 7.3: PROCEDURES
Create a quick Guide for the 9 procedures found
in the text on page 186. (This may become
homework if you do not finish).
 Sketch a DNA “gel” in lab notebook to record
your results. Label each well with the sample
that will be placed there.
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LAB 7.3: CONCLUSION QUESTIONS
1.
2.
3.
Which suspect’s DNA profile matches the crimescene DNA evidence?
Justify your answer, referring to the DNA
fingerprint and the DNA standard marker as a
reference.
Explain what other testing could be done using
DNA gel electrophoresis to increase the
probability that a person's DNA either matches
or does not match the evidence?
REST OF CLASS PERIOD
Finish
the Chapter 7 Review at
the back of the chapter  you
will get a study guide for the
DNA Fingerprinting Quest
tomorrow.
 If you have time  read two of
the case studies at the back and
summarize them in 2 sentences
in your notebook.