FLYING BLOOD: Using STEM-based Forensic Trajectory Analysis
of Blood Stains to Reconstruct a Crime!
Saturday, April 13th, 2013
3:30 AM – 4:30 PM
Marriott River Center, Salon D
Perform a forensic reconstruction of a crime scene based on the measurement of blood stains and the calculation
of the trajectory of the blood.
Presenter: Michael J.V. Lazaroff E-mail: Michael_Lazaroff@westport.k12.ct.us
Co-creator:
David Rollison E-mail: David_Rollison@westport.k12.ct.us
Staples High School, Westport, CT
SUBJECT: Forensics, Integrated Science
GRADE LEVEL: High School & Middle School
Rationale
The crimes that appear on CSI and Law and Order that so intrigue our student usually involve murder. So many
of those shows include scenes in which someone analyzes the blood stains in a crime scene to determine the
nature of the crime. When I do this lab in class, we use defibrinated (which limit the clotting, and allows me to
use a sample over a longer period of time) animal blood, which is really the best way to present this lab. Given
the difficulty in bringing blood on an airplane, we will be doing the next best thing, which is to use a sample of
simulated blood (this one is from WARD’S, and the MSDS sheet is included in the full handout online). If you
do so, get one for spatter activities, rather than that for blood typing, as it may not spatter quite as well. I have
also done this lab with latex paint, but it is important to water the paint down a bit.
After a brief introduction, we will go straight into the activity. The best way to get a sense of how to run this
activity is by doing it yourself! The handout distributed during the presentation will be limited to the blood
spatter analysis activity; not all of the pages shown in this presentation are in the handout distributed during this
workshop (although the links can be found on the bottom of each page), so please be sure to go to either the
NSTA site, or the website below to get them:
http://shs.westport.k12.ct.us/mjvl/lazaroff/nsta.htm
NOTE: Much of the information for each of the sections below can be found on individual web pages on our
website, The Crime Lab: Staples High School Forensics. URL: http://shs.westport.k12.ct.us/forensics/default.htm I
have also included much of this information in the FULL handout on the NSTA website, and I have included
instruction below to help you find them on the NSTA site. Please go there and download the FULL
presentation.
Please note, as this activity is not being presented by a vendor, I would appreciate it if all of the materials
(which are on loan from my department) are returned at the end of this workshop. THANK YOU!
Blood Spatter Analysis
Name: _________________________________________ Date: ___________________ Period: _____
Return to The Crime Lab
Introduction Materials Procedure Data/Results Conclusion
Introduction:
Just like gun powder residues and paint chips, blood spatter can help investigators piece together the events of a crime. Generally
speaking, when blood spatter is found someone has been bleeding. From the shape and size of the blood drops, investigators can
sometimes reconstruct what happened during the attack. Since real human blood carries the risk of blood-borne pathogens, it is not used
in school, so we will be using red latex paint. The paint will simulate the physical characteristics of human blood, not only in terms of
color, bit in terms of consistency as well.
Categories of Blood Stains:
Passive - formed due solely to the effect
of gravity. These include drips, pools, and
clots (the last two being from venous
bleeding).
Projected - due to a force, either within the
transfers ink from an inkpad onto another body (internal, such as arterial spurts, as
surface, and the ink stain takes the shape of seen above), or from outside the body
the stamp, blood from a hand or shoe will (external, such as cast off), which is greater
than the force of gravity, thus allowing the
leave behind that impression.
blood to travel in a path other than merely
one due to gravity.
Transfer - similar to the way a stamp
Images from BLOODSTAIN PATTERN ANALYSIS TUTORIAL By: J. Slemko Forensic Consulting
Stain Size & Velocity of Projected Blood:
Low Velocity
Medium Velocity
High Velocity
Less than 5 feet/second
Stains larger than 4 mm
5 to 25 feet/second
Stains 1 - 4 mm
Over 100 feet/second
Stains smaller than 1 mm
Stain Shape, Direction, & Angle of Trajectory:
Direction of Travel
NOTE:
Angle of Trajectory
In this lab, you have the option
of calculating the trajectory, or
you may compare the stains
here with the angles we made in
class.
In a real crime scene, it would
be calculated.
TO SOLVE A BLOODSTAIN'S ANGLE OF IMPACT
10 mm Width / 20 mm Length = 0.5 = SIN of the Angle
ARC SIN of 0.5 = 30
The Angle of Impact is 30o
Images by Mr. Lazaroff
Calculate the Angle of Trajectory using the Interactive Web Page Below:
http://shs.westport.k12.ct.us/forensics/08-blood/blood_spatter_trajectory.htm
Convergence:
Sample Angles:
http://shs.westport.k12.ct.us/forensics/08-blood/bloodspatter_analysis.htm
Blood Spatter Analysis
Images from http://wardsci.com/images/pdf/color_blood_spatter_images.pdf
Image by Mr. Lazaroff
Materials:
1. Pre-made butcher paper with "blood" stains (using blood-red paint)
2. Paper and pencil for sketching the patterns
3. The samplers on index cards made during the initial Blood Spatter Sampler Activity
Procedure:
1. Compare your sampler to the unknown spatter pattern to see if you can determine the angle of the blood stains. Be sure to
note the number of each of the unknown patterns (1 - 4).
2. Using the angles you determined above, determine the direction from which the stains came.
3. Based on the overall patterns, determine how many individuals were involved.
4. Using the direction of the stains, determine the direction the individual(s) was/were traveling.
5. Based on all of the above, determine which individual, in the cases involving blood from more than one source, was the
attacker, and which was the victim.
6. Based on the patterns discussed in class, determine whether the blood was venous blood or arterial blood.
NOTE: Color cannot be used here, as we are using only one can of paint!
7. Based on the patterns discussed in class, determine whether the stains are passive, transfer or projected.
8. Based on the patterns discussed in class, determine the velocity of the projected spatter.
9. Based on the patterns discussed in class, determine the origin of the projected spatter (transfer impression, dripping
wound, spurt, GSW, back-spatter, spilled, etc.).
10. Based on the patterns discussed in class, determine the angle of the blood's impact. (Once again, you may either calculate
or compare the stain to the sample stains.)
11. Based on the patterns discussed in class, determine the convergence of the trajectories.
12. Based on the patterns discussed in class, describe the scenario of the crime. NOTE: Some scenarios have more to draw
upon than others.
13. Repeat the steps 1-12 with each of the three butcher paper scenarios.
FORENSICS: We give a new meaning to butcher paper!
http://shs.westport.k12.ct.us/forensics/08-blood/bloodspatter_analysis.htm
Blood Spatter Analysis
Data/Results:
Your data will be diagrams of each of the four patterns of blood stains, with arrows to indicate the direction of each individual's
movement, and descriptions of the angles of the impact for the blood stains in various areas, not to mention passive, transfer, projected
(include velocity due to stain size), origin of the spatter, convergence, etc.
Conclusion:
Your conclusion needs to illustrate, for each of the scenarios, how many individuals there were in each, and, using arrows, indicate the
direction of each individual's movement.
http://shs.westport.k12.ct.us/forensics/08-blood/bloodspatter_analysis.htm
Blood Stains by Source
Return to The Crime Lab
Go to Blood Components Go to Blood Spatter Sampler Activity
Go to Blood Spatter Analysis
Arteries & Veins
Blood stains vary by the vessel(s) that is/are the source of the blood. Venous stains (with the
blood from veins) contain darker blood (DARK RED, NOT blue!) which is deoxygenated (low in
Oxygen, high in Carbon Dioxide. Blood in veins travels under lower pressure, and the length of the
vessel's distance from the heart (in terms of how far the blood has traveled since it left the heart)
means that the blood is at very low pressure. This blood will flow slowly, and continuously, with
the volume per minute determined by the diameter of the vein itself (i.e., severing a larger vein will
lead to higher blood loss in a minute, than will a smaller vein).
Arterial blood (with the blood from arteries), on the other hand, is oxygenated, which means that
it contains more Oxygen, and less Carbon Dioxide, and the blood is BRIGHT RED. Since arteries
contain blood that is closer to the outward pumping action of the blood, with the pump behind the
blood, that blood is at a higher pressure.
SmartDraw image adapted by Mr. Lazaroff
Given that each contraction of the heart (systole) is followed by a relaxation of the heart
(diastole), your arterial blood pressure travels in waves. These crests and troughs of the waves
form the pair of numbers in the blood pressure reading you get at the doctor's office
(systolic/diastolic, and a good target for you is 120/70). Note the waves in the diagram below.
http://shs.westport.k12.ct.us/forensics/08-blood/bloodstains.htm
Blood Stains by Source
SmartDraw image adapted by Mr. Lazaroff
The implications of this higher pressure are important in terms of bleeding. Since the blood
travels in the arteries in waves of high and low pressure, the blood will travel out of the arteries (on
its way out of the body) in spurts! Once again, how fast you exsanguinate (bleed out) depends on
the diameter of the artery that is severed. All in all, you will bleed out faster from an arterial bleed
than from an equivalent venous bleed. For this reason, higher animals evolved with the arteries
deeper than the equivalent veins, and larger vessels (for both arteries and veins) deeper than smaller
vessels. This is why minor culinary mishaps -- Oops! I cut my thumb! -- aren't fatal!
(NOTE: The previous comments about Oxygen and Carbon Dioxide in both arterial and
venous blood apply to most arteries and veins in the body. All arteries go away from the
heart, and all veins go toward the heart. Given that, the pulmonary arteries, going to the
lungs, contain deoxygenated blood, and the pulmonary veins, returning from the lungs,
contain oxygenated blood.)
SmartDraw image adapted by Mr. Lazaroff
NOTE: The convention of using the colors RED & BLUE to differentiate human blood
http://shs.westport.k12.ct.us/forensics/08-blood/bloodstains.htm
Blood Stains by Source
and blood vessels is an old one, and Anatomy & Medical textbooks are lousy with such
images. That is why I used them above. Just don't forget your blood's true colors!
Blood Stains
Given what was discussed about venous and arterial blood, the look of the stain will be different.
Venous blood, at low pressure, is more likely to pool, especially in a victim who is lying down.
Arterial blood, at high pressure, is more likely to spurt, and in a stationary victim will produce a
wave-like pattern of crests and troughs.
Image from BLOODSTAIN PATTERN ANALYSIS TUTORIAL By: J. Slemko Forensic Consulting
Blood stains in a crime scene can take many forms, but they tend to fall into three categories:
passive, transfer, and projected.
Categories of Blood Stains:
Passive - formed due solely to the effect of gravity. These include drips, pools,
and clots (the last two being from venous bleeding).
Images from BLOODSTAIN PATTERN ANALYSIS TUTORIAL By: J. Slemko Forensic Consulting
Transfer - similar to the way a stamp transfers ink from an inkpad onto another
surface, and the ink stain takes the shape of the stamp, blood from a hand or shoe
will leave behind that impression.
http://shs.westport.k12.ct.us/forensics/08-blood/bloodstains.htm
Blood Stains by Source
Images from BLOODSTAIN PATTERN ANALYSIS TUTORIAL By: J. Slemko Forensic Consulting
Projected - due to a force, either within the body (internal, such as arterial spurts,
as seen above), or from outside the body (external, such as cast off), which is
greater than the force of gravity, thus allowing the blood to travel in a path other
than merely one due to gravity.
Image from BLOODSTAIN PATTERN ANALYSIS TUTORIAL By: J. Slemko Forensic Consulting
There are two patterns of projected blood spatter that deserve special mention. In the case of a
GSW (gun shot wound), if there is an exit wound, the bullet, at great speed, will travel out of the
body producing a very specific blood stain. Depending on the type of bullet used, exit wounds can
be quite a bit larger than the entry wound. Such an exit wound will tear through quite a large
number of blood vessels of different sizes. This will create a spray-like pattern on the surface
adjacent to the exit wound.
Image from BLOODSTAIN PATTERN ANALYSIS TUTORIAL By: J. Slemko Forensic Consulting
http://shs.westport.k12.ct.us/forensics/08-blood/bloodstains.htm
Blood Stains by Source
This is also known as high velocity blood spatter, meaning a force greater than 100 ft/sec. The
mist like appearance is due to the majority of stains being no larger than 1mm. Medium velocity
stains are caused by a force of 5 to 25 ft/sec, and leave stains 1 to 4 mm in size. Low velocity
stains are caused by a force of up to 5 ft/sec, and leave stains larger than 4 mm in size.
Lastly, in the case of either bludgeoning or cutting, weapons are often used repeatedly in a single
attack (as in multiple stab wounds). As it takes a while for blood to clot and dry, any blood on a
weapon will flow off the weapon easily, especially when the weapon is in motion, even more so
when the direction of sudden movement changes, as when a person swings a pipe backwards in
order to have more power on the next hit. When the pipe changes direction, now moving forward
in order to connect with the victim's skull another time, the blood that was on the pipe will
continue to travel backwards. This is basically due to the concept of inertia: an object in motion
will stay in motion, and an object at rest will stay at rest, unless acted upon by a force.
Image from BLOODSTAIN PATTERN ANALYSIS TUTORIAL By: J. Slemko Forensic Consulting
The backward motion of a pipe that is covered in blood involves not only the motion of the pipe,
but the motion of the blood as well. When the pipe changes direction and moves forward, there is
no force to stop the continued backwards motion of the blood that was on the pipe. In this way, a
pattern of backwards spatter will appear on adjacent surfaces behind the attacker. For reasons
beyond understanding, this backwards spatter is called . . . uh . . . back-spatter (a.k.a. cast-off).
The analysis of blood spatter patterns gets more complex when one realizes that not everyone
stays stationary when they are either the attacker or the victim. This also means that we need to be
concerned with how many different individuals blood is at the scene. To fully reconstruct the crime
scene, we need to do more than just determine the angle of the impact, but we also need to
determine the direction the blood traveled, and the possible direction(s) the individual(s) is/were
moving. Given the surface tension of the water in the plasma, which in itself makes up about 55%
of the blood, when a drop of blood falls, it will act quite similar to the way water falls.
http://shs.westport.k12.ct.us/forensics/08-blood/bloodstains.htm
Blood Stains by Source
Image by Mr. Lazaroff
It is important to remember that blood is made up of a fluid matrix known as plasma, and various
cells and cell fragments which are collectively known as formed elements. The plasma is roughly
half of the volume of blood (46 to 63%), and that 92% of the plasma is water, The formed
elements include red blood cells (RBC, a.k.a. erythrocytes), white blood cells (WBC, a.k.a.
leukocytes), and cell fragments used in clotting that are called platelets (a.k.a. thrombocytes). The
combination of the dissolved proteins in the water of the plasma, and the formed elements, makes
blood 5 times stickier (or more viscous) than water alone.
As we have seen numerous times before, accurate measurements are crucial. Unlike ballistic
trajectories, which can be determined by placement of a rod in a bullet hole, there are no such holes
in blood spatter. We can, however, determine the angle of the blood's trajectory using trigonometry.
Image by Mr. Lazaroff
Once you have the SIN of the angle, simply do an ARC SIN of that number (make sure your
calculator is set to DEGREES not radians, and that will give you the angle. For Example:
TO SOLVE A BLOODSTAIN'S ANGLE OF IMPACT
10 mm Width / 20 mm Length = 0.5 = SIN of the Angle
ARC SIN of 0.5 = 30
The Angle of Impact is 30o
Once we have determined the trajectories of the blood spatter, a technique similar to that used in
ballistics is used here to determine the point of origin. This does, however, get more complex than
the image below. Why? Well the image below involves only 2 dimensions, whereas the blood
exists in three.
http://shs.westport.k12.ct.us/forensics/08-blood/bloodstains.htm
Blood Stains by Source
Image by Mr. Lazaroff
To make things even more complex, the nature of the surface makes the stains harder to read.
Note the differences due to the surface upon which the blood fell:
Smooth, Ceramic
Tile Surface
Linoleum Floor
Surface
Rough Concrete
Surface
Image from BLOODSTAIN PATTERN ANALYSIS TUTORIAL By: J. Slemko Forensic Consulting
A Final NOTE: When blood clots, the platelets cause the formation of protein fibers
(fibin) which trap the blood cells. This is similar to what happens when paint dries, with
the latex paint being a mixture of pigments in a polymer base, with water. In this analogy,
the pigments are equivalent to the formed elements, the polymer is equivalent to the fibrin
(don't forget that proteins are organic polymers), and the water (the solvent) is equivalent
to the water in the plasma. When the blood clots, the cells are trapped by the fibrin, and
the water in the plasma evaporates away, very much the way the water in the latex paint
evaporates, leaving the pigments trapped in the polymer. Clots can also be an important
part of blood spatter analysis, although we won't be exploring that here.
FURTHER READING:
A Great Resource: BLOODSTAIN PATTERN ANALYSIS TUTORIAL
By: J. Slemko Forensic Consulting
http://shs.westport.k12.ct.us/forensics/08-blood/bloodstains.htm
Blood Spatter Patterns
Name: _________________________________________ Date: ___________________ Period: _____
Return to The Crime Lab
Introduction Materials Procedure Data/Results Conclusion
Introduction:
In this activity, we will be examining, under controlled conditions, how blood stains appear
when they are dropped at different angles, as would happen, for example, if blood from a
swinging axe were to be thrown downward against a wall. Since we will be using droppers to
drop the blood, the blood will always be falling at a 90° angle. In order to show the effect of
angle on the dripping "blood," we will have the poster board surfaces at an angle.
Materials:
1. Defibrinated (to prevent clotting) Bovine (Cow) blood
2. Beryl pipette
3. Rulers
4. Index cards
5. Protractors
6. Masking tape
7. Ring stands
Procedure:
1. Using the protractor, attach the ruler (using the masking tape) to the ring stand
at one of the following angles: (10°, 20°, 30°, 40°, 50°, 60°, 70°, 80°, 90°).
Each group will be assigned a different angle.
NOTE: 90° angle means that the surface is lying at a 90° angle to the falling
drop (i.e., a vertical drop onto a flat surface.
2. Remember: 1. the angle of the ruler + 2. the angle of impact = 90°. Thus a flat
index card + the vertical drop (which will always fall at 90°) = 90°. If the index
card is at a 60°angle, then the angle of impact = 30°.
http://shs.westport.k12.ct.us/forensics/08-blood/bloodspatter.htm
Blood Spatter Patterns
3. Label an index card with the angle you have been given.
4. Tape the index card about half way down the ruler.
5. Your teacher will come around and drip blood onto the index card.
6. Gently remove the card from the ring stand so as not to disturb the stain.
7. Your teacher will line up the cards on one of the lab tables, so that you may use
them for reference.
8. Once you are finished with the samplers, you are to observe a series of blood
spatter examples made earlier by your teacher. This is the next activity: Blood
Spatter Analysis.
Data/Results:
1. The 9 index cards you made. Make sure everything is well labeled.
Conclusion:
There is no conclusion for this activity.
http://shs.westport.k12.ct.us/forensics/08-blood/bloodspatter.htm
Right Triangle Trigonometry
Topic Index | Algebra Index | Regents Exam Prep Center
where A represents the angle of reference.
The formulas can be remembered by:
oh heck, another hour of algebra!
The formulas can be remembered by:
oscar had a heap of apples
There are many such memory tricks.
These formulas ONLY work in a right triangle.
The hypotenuse is always across from the right angle.
Questions usually ask for an answer to the nearest units.
You will need a scientific or graphing calculator.
1. Draw a picture depicting the situation.
2. Be sure to place the degrees INSIDE the
triangle.
3. Place a stick figure at the angle as a point of
reference.
http://www.regentsprep.org/Regents/math/ALGEBRA/AT2/Ltrig.htm
Right Triangle Trigonometry
4. Thinking of yourself as the stick figure, label
the
pposite side (the side across from you),
the
ypotenuse (across from the right angle),
and the djacent side (the leftover side).
5. Notice how the values on the sides of the
triangle "pair up". The h pairs with the 15,
the o pairs with the x, but the a stands alone.
The a has no companion term. This means
that the a is NOT involved in the solution of
this problem. Cross it out!
6. This problem deals with o and h which means
it is using sin A.
1. Place the degrees in the formula for angle A.
2. Replace o and h with their companion terms.
3. Using your scientific/graphing calculator,
determine the value of the left side of the
equation. (On most scientific calculators, press 35
first and then press the sin key. On most graphing
calculators, press the sin key first and the 35 second.)
4. Solve the equation algebraically. In this case,
cross multiply and solve for x. Or just
remember that if the x is on the top, you will
multiply to arrive at your answer. If x is on
the bottom, divide to arrive at your answer
(see next example).
5. Round answer to the desired value.
Set up the diagram and the formula in the same manner as was done in Example 1. You
should arrive at the drawing and the formula shown here.
http://www.regentsprep.org/Regents/math/ALGEBRA/AT2/Ltrig.htm
Right Triangle Trigonometry
Hint: If you are having a problem solving the Hint: Be sure your answer MAKES
equation algebraically, remember that when x is
on the bottom, you must divide to arrive at your
answer. The division is always "divide BY the
trig value decimal".
SENSE!!! The hypotenuse is always the
largest side in a right triangle. So, our
answer of 26.50 makes sense - it is bigger
than the leg of 20.
In this triangle, you were given the values in
black. You also know that the angle at B is 68º
because there are 180º in every triangle. By
repositioning your reference point, all of the
following are true.
See how to use your
TI-83+/TI-84+
graphing calculator
with beginning
trigonometry.
Click calculator.
Topic Index | Algebra Index | Regents Exam Prep Center
Created by Donna Roberts
Copyright 1998-2012 http://regentsprep.org
Oswego City School District Regents Exam Prep Center
http://www.regentsprep.org/Regents/math/ALGEBRA/AT2/Ltrig.htm
Components of Blood
Go to Bloodstains by Source
Return to The Crime Lab
Go to Blood Spatter Sampler Activity Go to Blood Spatter Analysis
NOTE: Much of this information is in the
Introduction to the Blood Spatter Sampler Activity.
Plasma = 46 to 63% (about 55%)
Plasma levels vary with s
Water = 92% of the plasma volume
Plasma Proteins (albumin, some hormones, etc.)
Nutrients, Wastes (including CO2), and hormones (steroid-based or amino
acid-based) are carried here as well
Electrolytes - these are what you have to replace if you have been vomiting or
have had diarrhea for too long (Think GatoradeTM or PedialyteTM)
http://shs.westport.k12.ct.us/forensics/08-blood/blood_components.htm
Components of Blood
NOTE: Knowledge of these levels is essential to toxicology.
Toxicology can do more than merely identify poisons or drugs in the
body, but they can measure the effects of drugs in the body, or the
effects of underlying disorders. What may appear to be a homicide
may, in fact, be a more natural death.
Formed Elements = 37 to 54% (about 45%)
RBC = 99.9% (anucleated) - Carry O2, and a small amount of the body's CO2
http://shs.westport.k12.ct.us/forensics/08-blood/blood_components.htm
Components of Blood
(Source; http://www.answers.com/topic/sir-charles-chaplin )
Image from http://www.popstarsplus.com/actors_charliechaplain.htm
WBC = Less than 0.1%
Types: Neutrophils,
Lymphocytes
Eosinophils,
Basophils,
Monocytes,
and
Platelets (Thrombocytes) = Less than 0.1% - Responsible for clotting
Platelets are called thrombocytes because a thrombus is a clot!
Thrombo - cyte
Blood clot - cell
NOTE:
Knowledge of the normal numbers of each type of cell is essential
to an understanding of blood disorders.
http://shs.westport.k12.ct.us/forensics/08-blood/blood_components.htm
Components of Blood
Too few RBC is one form of anemia.
Too few of certain WBC (T4 helper cells) could mean AIDS.
Too many WBC is called Leukocytosis.
Too many Monocytes is a sign of Mononucleosis (which has
nothing to do with kissing!)
A small increase in WBC number (mild leukocytosis) could be a
sign of an infection.
A LARGE in crease in WBC number (severe leukocytosis) could
be a sign of leukemia.
The PROTEINS and the FORMED ELEMENTS make blood 5X stickier
(more viscous) than water. That's what makes blood stains stick, not to
mention making them look so cool!
NOTE:
http://shs.westport.k12.ct.us/forensics/08-blood/blood_components.htm
Components of Blood
The damaged blood vessels release a chemical which causes
the platelets to adhere to the blood vessel wall.
The platelets form extensions which help them to trap other
platelets (see the image above).
Blood clots form more easily in veins and capillaries, because
blood in those vessels is under lower blood pressure.
Higher blood pressure, which is found in arteries, slows the
formation of the fibrin network, which in turn prevents the
trapping of the RBC.
It is therefore easier to exsanguinate from an arterial bleed,
although any injury to a large vessel will still make it hard to
clot.
Pressure applied to an injury will prevent blood from leaving
the vessel, thus allowing the clot to form more easily. A
tourniquet, which ties off the blood flow along a limb, will have
a similar effect: less blood flow, the faster the clotting.
In order to make arterial bleeds more rare, we evolved to have
our arteries deeper than our veins, which, in turn, are deeper
than the superficial capillaries of our skin.
This is similar to what happens when paint dries, with the latex paint being a
mixture of pigments in a polymer base, with water. In this analogy, the
pigments are equivalent to the formed elements, the polymer is equivalent to
the fibrin (don't forget that proteins are organic polymers), and the water (the
solvent) is equivalent to the water in the plasma. When the blood clots, the
cells are trapped by the fibrin, and the water in the plasma evaporates away,
very much the way the water in the latex paint evaporates, leaving the pigments
trapped in the polymer.
NOTE: For a quick activity, we can use either prepared blood slides or the students can
prepare their own using the defibrinated bovine blood we ordered.
http://shs.westport.k12.ct.us/forensics/08-blood/blood_components.htm
Blood Type Lab
Blood Type Lab
Name: _________________________________________ Date: ___________________ Period: _____
Return to The Crime Lab
NOTE: There are multiple labs available using artificial blood; any of them will suffice. I have adapted the information from one of them
below.
Part I: ABO
I. Problem: "Who's the father?"
II. Hypothesis: (Predict!) ________________________________
III. Materials & Procedure - Part I: ABO
(4 slides, 4 "blood" samples, anti A serum, anti B serum,
toothpicks)
Jane C. Public Baby: John Q. Public, Jr.
John Q. Public,
John Q. Citizen
or
Father?:
Sr.
+
Mother:
1. Place your slide over the cicrles of the person’s whose "blood"
you are testing.
2. Place one drop of "blood" on the center of each circle.
3. Place one drop of anti A serum on the anti A circle.
Set aside one toothpick for this.
4. Place one drop of anti B serum on the anti B circle.
Set aside another toothpick for this.
5. Mix for 2 minutes, observe the results, and circle:
NOTE: One Toothpock for EACH test
+ or -, and the "blood" type A B AB O
(Negative)
Doesn't
Contain
Antigen
Be careful not to CONTAMINATE the
droppers . . .
(Positive)
Does
Contain
Antigen
IV. Data - Part I: ABO
Who's the Father?
John
Jane
Q.
C.
Public,
Public
Sr.
John
John
Q.
Q.
Public,
Citizen
Jr.
Anti A
Anti B
Anti A
Anti B
+ -
+ -
+ -
+ -
Blood
Type
Blood
Type
A B
AB O
A B
AB O
Anti A
+ -
Anti B
+ -
Anti A
+ -
Anti B
+ -
Blood
A B
Type
AB O
Blood
A B
Type
AB O
V. Questions - Part I: ABO
1. Jane is John C. Public, Jr.'s mother. John Q. Public, Sr. claims that he is not John Jr.'s father and suspects that John Q. Citizen is the
father. Could John, Sr. be John, Jr.'s father? Explain.
2. Could John Q. Citizen be John, Jr's father? Explain.
Part II: Rh
I. Problem: "Is the baby AT RISK?"
http://shs.westport.k12.ct.us/forensics/blood_type_lab2.htm
Blood Type Lab
II. Hypothesis: (Predict!) ________________________________
III. Materials & Procedure - Part II: Rh
(3 slides, 3 "blood" samples, anti Rh serum, toothpicks)
1.
2.
3.
4.
Place your slide over the cicrles of the person’s whose "blood" you are testing.
Place one drop of "blood" on the center of each circle.
Place one drop of anti Rh serum on the circle.
Mix for 2 minutes, observe the results, and circle: Rh + or Rh -
Be careful not to CONTAMINATE the
droppers . . .
IV. Data - Part II: Rh
Ms. Phyllis Doe
Mr. Horatio Doe
Lil' Binky Doe
Rh + Rh -
Rh + Rh -
Rh + Rh -
V. Questions - Part II: Rh?
1. What is Erythroblastosis fetalis?
2. Is Lil' Binky Doe at risk for this? Why or why not?
VI. Conclusion:
There is no conclusion for this activity.
http://shs.westport.k12.ct.us/forensics/blood_type_lab2.htm
How much do you really know about BLOOD?
Just some of the facts included in
BLOOD: An Epic History of Medicine and Commerce
by Douglas Starr
Publisher: Harper Perennial; 1 edition (March 7, 2000)
ISBN-10: 0688176496
ISBN-13: 978-0688176495
Blood conveyed strength to the Romans which is why gladiators were said to have drunk the blood of fallen
opponents.
The Bible mentions blood more than 400 times.
The Old Testament law specifically forbids the consumption of blood, which is why Jehovah's Witnesses refuse
transfusions.
The first transfusions were not used to treat blood loss, but insanity.
The first documented blood transfusion took place in 1667 when one of Louis XIV's doctors infused calf's blood
into a madman. On the third try, the patient died--not from the transfusion as it turned out--but because his wife
had been secretly poisoning him.
Blood-letting is the longest running tradition in medicine, lasting some 2500 years, although there was never
any proof it worked.
When George Washington came down with strep throat at age 67 he insisted that his doctors copiously bleed
him. Over a period of two days they removed nine pints of his blood. It killed him.
It wasn't until 1900 that blood types were discovered.
It was not until 1915 that doctors learned how to keep blood from clotting long enough to make it possible to
transfuse from one person to another.
Blood banks were actually invented by the Soviets as a way of storing blood from cadavers which they used
later for transfusions.
It was during World War II that blood truly became mobilized and used as a strategic materiel.
World War II saw the first industrial processing of blood derivatives, including the production of freeze-dried
plasma and components such as gamma globulin and albumin. Much of this work was done at a semi-secret lab
at Harvard.
The Nazis were so obsessed with blood purity that they ran critically short of blood during the war, with
thousands dying for lack of blood.
In occupied Amsterdam, the Dutch set up a clandestine plasma plant in the Amstel brewery. The Germans
never caught on.
Blood and its plasma based derivatives became commercial commodities in the years following WWII.
The blood business is split into two parts--the red blood and plasma sectors.
In past years, drug firms set up "plasma mills" in America's skid rows, buying from residents, who often
included drug addicts and indigents.
The information below was updated, and reworded to make the price comparison more current:
A barrel of oil cost about $94.52 on today's marketplace (April 4th, 2013, as per http://www.oilprice.net/, the same quantity of blood (1 barrel of oil = 42 gallons. 1 U.S. gallon = 3.78 liters, therefore
1 barrel of oil = 159 liters) would cost $ 63,621.18 (April 4th, 2013, as per
http://www.cockeyed.com/science/gallon/liquid.html, which was undated, and unconfirmed).
The global plasma business is worth about 5 billion dollars a year. The blood trade can be estimated at about 13
billion dollars.
The world wide tragedy of hemophiliacs who have contracted HIV from medical injections is the worst
medically induced calamity in history and has never been fully reported by the media.
When an American blood-screening test for the AIDS virus was announced the French government delayed
approval so a French company could gain a share of the market.
Government and corporate officials in Japan actively covered up the fact that AIDS had infected its hemophilia
population, and distributed material they knew to be contaminated. The top blood-banking officials were later
sent to jail.
Almost every country, except the U.S., has passed some kind of compensation package for hemophiliacs and
transfusion recipients who contracted AIDS from blood or its derivatives
Currently we are experiencing quite a problem with Hepatitis C. Blood has been screened for the virus since
1990. But since the disease takes years to manifest symptoms, many people have contracted the disease but still
do not know it.
Blood undergoes a battery of 8 screening tests for infectious diseases. Testing alone costs $25.00 to $30.00 a
pint, a significant percentage of the unit's full price of $145.00 to $200.00. (Amounts unverified, and w/o date).
Currently most estimates put the odds of contracting HIV through transfusions at about one in 450,000 which,
considering most patients receive multiple units puts the risk about one in 90,000.
The risk of new diseases is growing due to ecological disruption, migration, and global jet travel.
One of the unfortunate results of blood scandals is that Americans trust blood-bankers less than they used to and
are disinclined to donate. We are constantly facing blood shortages.
Several companies are currently pursuing a formula for artificial blood. Several of these formulations have gone
to clinical trials but none have yet been FDA approved. Research continues.
An e-mail to the makers of TIDE:
I am writing to say what an excellent product you
have. I've used it all of my married life, as my Mom
always told me it was the best. Now that I am in my
fifties I find it even better!
In fact, about a month ago, I spilled some red wine
on my new white blouse. My inconsiderate and
uncaring husband started to belittle me about how
clumsy I was, and generally started becoming a pain
in the neck. One thing led to another and somehow I
ended up with his blood on my new white blouse!
I grabbed my bottle of Tide with bleach alternative, to
my surprise and satisfaction, all of the stains came
out! In fact, the stains came out so well the
detectives who came by yesterday told me that the
DNA tests on my blouse were negative and then my
attorney called and said that I was no longer
considered a suspect in the disappearance of my
husband.
What a relief! Going through menopause is bad
enough without being a murder suspect!
I thank you, once again, for having a great product.
Well, gotta go, have to write to the Hefty bag people.