Unit One

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The Mystery Begins…
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

Lesson 1.1
Investigating
the Scene
Lesson 1.2
DNA Analysis
Lesson 1.3
The Findings




What can be done at a scene of a mysterious
death to help reconstruct what happened?
How do the clues found at a scene of a
mysterious death help investigators determine
what might have occurred and help identify or
exonerate potential suspects?
How do scientists design experiments to find the
most accurate answer to the question they are
asking?
How are bloodstain patterns left at a crime
scene used to help investigators establish the
events that took place during a crime?
Biomedical Science
Control Group
Dependent Variable
Experiment
Forensic Science
Hypothesis
Independent Variable
Negative Control
Personal Protective Equipment
Positive Control
It was a hot, 92°F summer morning. The emergency call came in at 9:45 am. A man
contacted the police to report that he was worried about his next door neighbor, a
woman named Anna Garcia. He informed the police that he had spoken to Anna the
previous morning when he saw her walking her dog around 6:30 am. He noted that she
was wearing a sweater even though they were currently experiencing a heat wave. He
decided to call the police this morning because Anna’s dog had been barking excitedly
for the last two hours (which is extremely unusual in this normally quiet suburban
neighborhood). He tried to call Anna on the telephone, but no one answered. Next he
tried ringing her doorbell, but there was no answer. The 911 operator notified the local
police and the emergency medical technicians (EMT). Both the police and the EMT
arrived at the scene at 9:56 am. The front door had to be broken down. Upon entering
the house, they found Anna lying face down in the entry hallway. It was a comfortable
73˚F inside the house. The EMT determined that Anna was dead. The police immediately
notified your team of crime scene investigators as well as the medical examiner, both of
whom were dispatched to the house. Has a crime been committed? The mystery
begins! It is your job to put together as many pieces of information as you can find.
(Don’t worry – the dog was taken to the home of close family friends and is
doing just fine.)
Three Ring Binder- tabs for each
unit, protocols and rubrics,
career journals and for
community service
 Lab book- Notes on minilectures, experiments, activities
and projects

 Date
 Name of lecture/activity
 Name of partners/group

USB-Folders for each unit for all
assignments within that unit
New Program!
 Very Cool!
While
Learn
with a partner…
you
work: Photos
& Web
Profiles!





Read the
introduction
Get organized!
Search
methods…
Examination
 INVESTIGATE
EVERY PART
OF THE SCENE
Victim's Stats
 Age: 38
 Weight:
165
 Height: 64
Inches
 Race:
Hispanic
 Sex:
Female

Persons of Interest



Documentation
 End-of-text
 In-text (later)
Validates our claims
 Discuss later in detail
Decreases Plagiarism
 No cut and paste
 Grounds for dismissal





Career Journals
1. 911 Operator
2. EMT
3. Crime Scene
Investigator
Guidelines
Rubric
Example
Wepage
Work as a
Forensic
Scientist
Process evidence to
get answers and
identify potential
suspects!
But…
safety first.


Specialized clothing or
equipment worn by an
employee for protection
against infectious
materials (OSHA)
Factors Influencing PPE
Selection:




 Type of exposure
anticipated
 Durability and
appropriateness for the
task
 Fit


Gloves – protect hands
Gowns/aprons – protect
skin and/or clothing
Masks and respirators–
protect mouth/nose
Respirators – protect
respiratory tract from
airborne infectious
agents
Goggles – protect eyes
Face shields – protect
face, mouth, nose, and
eyes
EXPOSURE 1
EXPOSURE 2
Gloves – Use when touching
blood, body fluids, secretions,
excretions, contaminated
items; for touching mucus
membranes and non-intact
skin
 Gowns – Use during
procedures and patient care
activities when contact of
clothing/ exposed skin with
blood/body fluids, secretions,
or excretions is


Mask and goggles or a face
shield – Use during patient
care activities likely to
generate splashes or
sprays of blood, body
fluids, secretions, or
excretions
• Keep gloved hands away from face
• Avoid touching or adjusting other PPE
• Remove gloves if they become torn; perform hand hygiene before donning
new gloves
• Limit surfaces and items touched
• Wash hands immediately after removing PPE.
• Use soap and water or use an alcohol-based hand rub

Forensic Chemist
 Presumptive tests
▪ Type of substance
 Confirmatory tests
▪ Exact substance

Can we identify the
unknown pills next to
our victim?





Follow specific directions for how to perform
the analysis at each station.
Fill out the Activity 1.1.4 Student Response
Sheet as you work through each station.
Revise your theories of what happened to
Anna.
Consider all analyzed evidence and what the
evidence suggests at this time.
Include any updated theories or information
to your Investigative Notes.


Experiment- A research
study conducted to
determine the effect
that one variable has
upon another variable.
Researcher maximizes
control over as many
aspects of the
environment as possible
in order to prove that
one variable affects
another variable.

Reliable:
 An experiment in which
another researcher can
perform exactly the same
experiment and generate
similar results.

Valid:
 An experiment in which the
results accurately describe
the real world.


Reliable- Another researcher can perform exactly
the same experiment and generate similar results.
Valid-Results accurately describe the real world.
Formulate a
hypothesis.
Identify
the
problem.
Design the
procedure to
be used to test
the
hypothesis.
Carry out the
experimental
procedure.
Analyze the
data and
observations.

State the question you are trying to answer
 Specific
 Measurable
 Example Problem: Does InstaGrow Fertilizer make
plants grow larger than plants grown without
InstaGrow Fertilizer?



The hypothesis is a clear prediction of the
anticipated results.
If…then…
Indicates the independent and dependent
variables in the experiment.
 Independent Variable: varied or manipulated,
presumed cause
 Dependent Variable: measurable response, not
manipulated, presumed effect
Does ___________ cause/affect ___________?
Independent Variable
Dependent Variable
Example Problem: Does InstaGrow Fertilizer
make plants grow larger than plants grown
without InstaGrow Fertilizer?
Does InstaGrow Fertilizer cause/affect plant growth?
▪ Independent Variable: InstaGrow Fertilizer
▪ Dependent Variable: Plant Growth

If fertilizer affects plant growth in a positive way then…
The plants treated with InstaGrow Fertilizer will
grow larger than the plants not treated with
fertilizer.


IV: use of the fertilizer
DV: plant growth
 The prediction of the results is clearly stated
 The variables are clearly indicated

Step-by-step detail for how to perform the
experiment
 Every detail is important
 Experiment must be replicable

All variables/conditions in an experiment need
to be kept exactly the same (control variables)
 Except the independent variable (IV)
 Ensures that the IV is the only variable affecting the
result
Safety concerns
Materials used
Control group
Control Variables: Environmental conditions that need to be consistent
• Most difficult!!!
How data will be collected and recorded
How many trials will be performed



Experiments need to include a control group
Independent variable being tested is not
applied so that it may serve as a standard for
comparison against the experimental group
where the independent variable is applied.
Example: The control group for the fertilizer
experiment is the group of plants NOT given
the InstaGrow fertilizer.
POSITIVE CONTROL


Group expected to have
a positive result
Allows the researcher to
show that the
experimental set up was
capable of producing
results
NEGATIVE CONTROL


Control groups where
conditions produce a
negative outcome
Identify outside
influences which may be
present that were not
accounted for
Scientist #1:
 The 10 plants grew an
average of 40 inches each.
Therefore, Scientist #1
concluded that InstaGrow
Fertilizer makes plants
growLARGER
larger. THAN
WHAT????
Scientist #2:
 The 5 plants given
InstaGrow Fertilizer grew
an average of 39 inches
each, while the 5 plants
NOT given InstaGrow
Fertilizer grew an average
of 41 inches each.
Therefore, Scientist #2
concluded that InstaGrow
Fertilizer does NOT make
plants grow larger.
Two scientists wanted to test to determine whether
InstaGrow Fertilizer makes plants grow larger.
Scientist #1:
 Ran the experiment with 10 plants.
 Planted each plant in the same
amount and type of soil.
 Placed each plant in comparable
environments.
 Gave each plant the same amount
of sun each day.
 Gave each plant the same amount
of water each day.
 Gave each plant the same amount
of InstaGrow Fertilizer.
 Let grow for 30 days.
Scientist #2:
 Ran the experiment with 10 plants.
 Planted each plant in the same
amount and type of soil.
 Placed each plant in comparable
environments.
 Gave each plant the same amount of
sun each day.
 Gave each plant the same amount of
water each day.
 Gave 5 plants the same amount of
InstaGrow Fertilizer, while 5 plants
received no fertilizer.
 Let grow for 30 days.
Formulate a
hypothesis.
Identify
the
problem.
Design the
procedure to
be used to test
the
hypothesis.
Carry out the
experimental
procedure.
Analyze the
data and
observations.

Carry out Procedure
 Follow step-by-step procedure.
 Collect the data in data tables.
 Make and record observations.

Analyze data
 Logically and clearly present all data and
observations in the form of graphs and charts.
 Clearly and concisely analyze all data and
observations.

Write a conclusion statement directly related
to the original hypothesis
 For example: “The hypothesis was correct…”


Explain the rationale for the conclusion and
clarify any details.
Discuss any possible sources of error.
 Anything that might have affected the results of
the experiment.
Change your
hypothesis.
 Re-design the
procedure because of
design flaws.
 Develop new questions
based on the work in
this experiment.
 Move on to a new or
related research topic.
 Why do some types of
fertilizer work better
than others…?


Why is it important (Brainstorm)


Temperature & Body
Cooling
Partners & Assigned
Temperatures:





How’d we do in determining Anna’s Time of
Death?
List potential answers…
Approximate
time
Glaister Equation:
(98.4 – measured
rectal
death:
temperature)/1.5 =ofapproximate
hours since
11:00am – 4 hrs =
death
7:00am
The medical examiner measured Anna’s rectal
temperature to be 92.4˚ at 11:00am.
98.4−92.4
= 4 hrs since death
1.5
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

Blood is powerful evidence!
What can blood can tell us?
What can blood splatter tell us?



How can we determine if the blood at the
crime scene was the result of an accident or
foulplay
Determine if blood at the scene was dropped
from Anna’s height (indicating that she might
have been struck) or from a lower height
(indicating that she may have been hit while
down or on her way down).
Design an experiment to provide evidence for
the case

Determine if blood at the scene
 Dropped from Anna’s height
 Indicates…
 Dropped from a lower height
 Indicates…

Design an experiment to provide evidence for
the case
AM CLASS
PM CLASS
What can be done at a scene of a
mysterious death to help reconstruct
what happened?
 How do the clues found at a scene of
a mysterious death help
investigators determine what might
have occurred and help identify or
exonerate potential suspects?
 How do scientists design
experiments to find the most
accurate answer to the question they
are asking?
 How are bloodstain patterns left at a
crime scene used to help
investigators establish the events
that took place during a crime?

Biomedical Science
Control Group
Dependent Variable
Experiment
Forensic Science
Hypothesis
Independent
Variable
 Negative Control
 Personal Protective
Equipment
 Positive Control










Lesson 1.1
Investigating
the Scene
Lesson 1.2
DNA
Analysis
Lesson 1.3
The Findings
What is DNA?
How do scientists isolate DNA in order to study
it?
 How does DNA differ from person to person?
 How can tools of molecular biology be used to
compare the DNA of two individuals?
 What are restriction enzymes?
 What are restriction fragment length
polymorphisms?
 What is gel electrophoresis and how can the
results of this technique be interpreted?


Adenine
Chromosome
Cytosine
Deoxyribonucleic Acid (DNA)
Gel Electrophoresis
Gene
Guanine
Helix
Model
Nucleotide
Restriction Enzyme
Restriction Fragment Length Polymorphisms (RFLPs)
Thymine



SFU Museum
The Real Fugitive
How can blood ID a
suspect or victim?
1.
2.
3.
4.
5.
6.
Genetic evidence is obtained
The DNA is EXTRACTED
The DNA is amplified by PCR
Investigators cut the DNA in specific
places called using RESTRICTION
ENZYMES
The size and number of the DNA
fragments are visualized using GEL
ELECTROPHORESIS
The DNA evidence can be matched to a
suspect’s DNA due to Restriction
Fragment Length Polymorphism or
RFLP



Deoxyribonucleic Acid
Hereditary material
Nucleotides
 Sugar molecule
 Phosphate group
 Nitrogenous base
▪ A, T, C & G
▪ Sequence determines traits
▪ Form double helix






Inheritance
Disease
Paternity
Drugs/Medicine
Crime
Evolution

Take a pic when you’re finished!
1.
Genetic evidence is obtained (blood, saliva,
hair)
2.
The DNA is EXTRACTED
3.
The DNA is amplified by PCR
Investigators cut the DNA in specific places
called using RESTRICTION ENZYMES
The size and number of the DNA fragments
are visualized using GEL
ELECTROPHORESIS
The DNA evidence can be matched to a
suspect’s DNA due to Restriction Fragment
Length Polymorphism or RFLP
4.
5.
6.
How do scientists isolate
DNA in order to study it?
 If all the DNA in our body
was linked end-to-end,
how long would the
molecule be?
 Must EXTRACT the DNA
from chromosomes and
separate it from other
materials inside cells



We are going to extract DNA today!
Follow directions CLOSELY- STEP BY STEP

Cell lysis buffer- Lyse cell membranes
 Detergent- Break apart lipids and proteins
 Salt- Increase solute concentration OUTSIDE of the
cell
 Baking soda- Sodium bicarbonate controls pH- it’s a
“buffer”

Ethanol- Less polar than water
 Adding ethanol to solution disrupts the charges by
water
 If enough ethanol is added, the electrical attraction
between phosphate groups and any positive ions
present in solution becomes strong enough to form
stable ionic bonds and DNA precipitation
1.
2.
Genetic evidence is obtained (blood, saliva,
hair)
The DNA is EXTRACTED
3.
The DNA is amplified by
PCR
4.
Investigators cut the DNA in specific places
called using RESTRICTION ENZYMES
The size and number of the DNA fragments
are visualized using GEL
ELECTROPHORESIS
The DNA evidence can be matched to a
suspect’s DNA due to Restriction Fragment
Length Polymorphism or RFLP
5.
6.
Amplifies the number of copies of a specific region of
DNA, in order to produce enough DNA to be adequately
tested
 Named after the enzyme, polymerase, which copies
DNA in cells
 Completed in a thermal cycler.
 Used for:








Medicalandbiologicalresearch
Cloning
Diagnosisofhereditarydiseases
Identificationoffingerprints
Forensic sciences
Paternitytesting
Diagnosisofinfectiousdiseases
1.
2.
3.
Genetic evidence is obtained (blood, saliva,
hair)
The DNA is EXTRACTED (we’ve done this)
The DNA is amplified by PCR
4.
Investigators cut the DNA
in specific places called
using RESTRICTION
ENZYMES
5.
The size and number of the DNA fragments
are visualized using GEL
ELECTROPHORESIS



With enough
DNA…detection is
possible
Restriction Enzymes:
Molecular scissors that
cut DNA in specific
location based on the
code (A,T,C,G)
Differences and
similarities are exposed
when they are cut in the
same place
1.
2.
3.
4.
Genetic evidence is obtained
The DNA is EXTRACTED
The DNA is amplified by PCR
Investigators cut the DNA in specific
places called using RESTRICTION
ENZYMES
5.
The size and number of
the DNA fragments are
visualized using GEL
ELECTROPHORESIS
6.
The DNA evidence can be matched to a



Visulaize the DNA
fragments and sort
them according to size
DNA samples are
loaded into a gel and
exposed to electrical
currents
The DNA fragments are
then stained with a dye
and can be observed as
lines or bands in the gel
1.
2.
3.
4.
Genetic evidence is obtained
The DNA is EXTRACTED
The DNA is amplified by PCR
Investigators cut the DNA in specific
places called using RESTRICTION
ENZYMES
5.
The size and number of
the DNA fragments are
visualized using GEL
ELECTROPHORESIS
6.
The DNA evidence can be matched to a
4.
5.
6.
Investigators cut the DNA in specific places called using
RESTRICTION ENZYMES
The size and number of the DNA fragments are visualized
using GEL ELECTROPHORESIS
The DNA evidence can be matched to
a suspect’s DNA due to Restriction
Fragment Length Polymorphism or
RFLP
A
B
Restriction
Enzymes
Length Polymorphism
= Difference in length
of fragments
Restriction
Fragment Length
Polymorphism
(RFLP)
http://users.rcn.com/jkimball.ma.ultranet/Bi
ologyPages/R/RFLPs.html.
B
A


We are going to go through these steps using
evidence from our crime scene…
Can we find our suspect? Good luck!

Finish with a career journal on a DNA Analyst







What is DNA?
How do scientists isolate DNA in
order to study it?
How does DNA differ from
person to person?
How can tools of molecular
biology be used to compare the
DNA of two individuals?
What are restriction enzymes?
What are restriction fragment
length polymorphisms?
What is gel electrophoresis and
how can the results of this
technique be interpreted?













Adenine
Chromosome
Cytosine
Deoxyribonucleic Acid
(DNA)
Gel Electrophoresis
Gene
Guanine
Helix
Model
Nucleotide
Restriction Enzyme
Restriction Fragment
Length Polymorphisms
(RFLPs)
Thymine



Lesson 1.1
Investigating
the Scene
Lesson 1.2
DNA Analysis
Lesson 1.3
The Findings






What is an autopsy and how can it be used to
determine the cause of death?
How can the manner of death be determined?
Why is confidentiality of patient information
important?
Who should keep patient information
confidential?
Is there ever a time when patient confidentiality
should be broken?
What biomedical science professionals are
involved in crime scene analysis and
determination of manner of death?
Autopsy
Bibliography
Citation
Documentation
Health Insurance Portability and Accountability Act (HIPAA)
Medical Examiner
Based on what we know thus far, what are some
possible causes for the death of the woman?
 Brainstorm with evidence board

Watch Dr. G:
Tools of the
Trade
 Do an autopsy
online

http://australianmuseu
m.net.au/interactivetools/autopsy

Complete 1.3.1
Organs are classified into systems (brainstorm!)
Problems with one body system can have serious
effects on others (brainstorm!)
 To diagnose a problem or determining cause of death
many pieces of information must often be linked
together before a conclusion can be reached


HIPAA: Health Insurance
Portability and
Accountability Act
 1996- standards for
health care related
electronic transactions
 mandates federal privacy
protections for certain
individually identifiable
health information

Professionals Must…
 Take all precautions necessary
 Not to speak about patients with any identifiable information with
anyone other than other professionals working with the patient
 Not leave patient in public space unattended
 Avoid being overheard and limit shared information
 Professionals May…
 Disclose PHI to a family member or other person involved when the
individual is present during the disclosure
 Communicate with patients regarding their health care, including
through the mail or by the phone
 Leave messages with family members, on voice mail, etc. with
patient consent


Regulates how medical professionals and
other people use and disclose certain
individually identifiable health information
(protected health information- PHI)
 Name, address, birth date, social security number,
 Past, present, future physical/mental health
 Health care services provided to the individual
 Past, present, or future payment
1.
2.
3.
4.
5.
6.
7.
Payment of benefits or
health coverage
Public health
Workman’s Comp
Legal proceedings
Law enforcement
Unable to make
medical decisions
Disaster relief
Assisting coroners or
medical examiners

Formal Case Report (I’ll give you a template)




Introduction
Summary of Findings
Conclusion
At least two figures:
▪ Inspiration
▪ Table
▪ Graph

Careers Journals
 Medical Examiner
 Toxicologist
 Morgue Assistant
1.
2.
3.
4.
5.
6.
What is an autopsy and how can it
be used to determine the cause of
death?
How can the manner of death be
determined?
Why is confidentiality of patient
information important?
Who should keep patient
information confidential?
Is there ever a time when patient
confidentiality should be broken?
What biomedical science
professionals are involved in crime
scene analysis and determination of
manner of death?






Autopsy
Bibliography
Citation
Documentation
Health Insurance
Portability and
Accountability
Act (HIPAA)
Medical
Examiner
Study Guide
 Not for credit
 Just for you
 Portfolio
 Table of contents
 Check carefully
 Complete
 Exam
 Multiple choice (15%)
 Short answer (30%)
 Practical (30%)
 Essay (25%)

Download