students will investigate the characteristics of blood blood testing and bloodstain analysis
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Unit 6 serology

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Students will investigate the characteristics of blood, blood testing, and bloodstain analysis. Unit 6 serology. Erythrocytes Leukocytes Thrombocytes Plasma Antigen RBC WBC Rh Factor Bloodstain Pattern Analysis Surface Tension Low-velocity impact splatter (LVIS)

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vocabulary

Erythrocytes

Leukocytes

Thrombocytes

Plasma

Antigen

RBC

WBC

Rh Factor

Bloodstain Pattern Analysis

Surface Tension

Low-velocity impact splatter (LVIS)

Medium-velocity impact splatter (MVIS)

High-velocity impact splatter (HVIS)

Drip pattern

Cast off pattern

Swipe/smear pattern

Spurt pattern

Expirated pattern

Agglutinate (verb)

Luminol

Blue Star

Hydrogen peroxide

Kastle-Meyer

Passive spatter

Transfer spatter

Projected spatter

Vocabulary
identify the components and physical properties of blood

(ERYTHROCYTES, LEUKOCYTES, THROMBOCYTES, AND PLASMA)

Solid portion of the blood

A. Erythrocytes

1. Red blood cells (RBC).

2. Contain hemoglobin that transports the oxygen and carbon dioxide.

3. Concave in structure.

4. Approximately 30 trillion in the blood.

IDENTIFY THE Components AND PHYSICAL PROPERTIES OF BLOOD
identify the componets and physical properties of blood

B. Leukocytes

1. White blood cells (WBC).

2. Provide immunity for the body and produce antibodies.

3. There are 5 types of white blood cells.

4. Approximately 430 billion in the blood.

IDENTIFY THE COMPONETS AND PHYSICAL PROPERTIES OF BLOOD
identify the componets and physical properties of blood1

C. Thrombocytes

1. Platelets (pieces of larger cells).

2. Responsible of starting the clotting process by making fibrin to form a clot.

IDENTIFY THE COMPONETS AND PHYSICAL PROPERTIES OF BLOOD
identify the componets and physical properties of blood2

Liquid portion of the blood

A. Plasma

1. Fluid portion of the blood that carries the RBC, WBC, and platelets.

2. 55% of blood is the plasma.

3. Made up of 90% water and 10% metabolites (salt, ions, and proteins).

IDENTIFY THE COMPONETS AND PHYSICAL PROPERTIES OF BLOOD
antigens and antibodies that determine abo blood types and the rh factor

ABO blood classification system

A. Antigens

1. Proteins found on the surface of every RBC.

2. There are over 100 different antigens in the human blood.

3. Two of the antigens, labeled as A and B, are the ones used on the RBC surface to determine blood type.

ANTIGENS AND ANTIBODIES THAT DETERMINE ABO BLOOD TYPES AND THE Rh FACTOR
antigens and antibodies that determine abo blood types and the rh factor1

If antigen A is present a person is A blood type.

  • If antigen B is present a person is B blood type.
  • If both antigens A & B are present a person is AB blood type.
  • If neither antigens A & B are present a person is O blood type.
ANTIGENS AND ANTIBODIES THAT DETERMINE ABO BLOOD TYPES AND THE Rh FACTOR
antigens and antibodies that determine abo blood types and the rh factor2

Antibodies

    • Manufactures by some of the WBC and found in the blood serum.
    • Function is to attack any invader (antigen) that enters the bloodstream that does not belong in your system.
    • A person has antibodies again antigens that are not found on the surface of their own RBC.
  • Rh Factor (Rhesus factor)
    • Antigen found on the surface of a RBC.
    • If a person has the Rh antigen they are Rh positive (Rh+).
    • If a person does not have the Rh antigen they are Rh negative (Rh-).
ANTIGENS AND ANTIBODIES THAT DETERMINE ABO BLOOD TYPES AND THE Rh FACTOR
determine genetic probabilities using blood types

Punnet Squares: A parent passes on one of two genes for blood type to the offspring. One of two genes is also passed on for the Rh factor. In order to be recessive in type or Rh, BOTH genes must be recessive. Using a Punnet square can determine if a blood type is possible in an offspring. This is useful in many ways, one of the most common being paternity.

Determine genetic probabilities using blood types
determine genetic probabilities using blood types1

If a child’s blood type is AB+, the mother’s type is AB+ and the father’s type is O-, could the “father” be the genetic father?

Determine genetic probabilities using blood types

A

B

O

O

properties of blood

Blood VolumeOn average, accounts for 8 % of total body weight

5 to 6 liters of blood for males

4 to 5 liters of blood for females

A 40 percent blood volume loss, internally or/and externally, is required to produce irreversible shock (death).

A blood loss of 1.5 liters, internally or externally, is required to cause incapacitation.

Properties of blood
blood typing using saliva

Blood typing can be done on people who are called “secretors”

80% of the population are secretors.

A secretor is a person who has the gene to secrete blood type substances (A, B & H)in a soluble glycoprotein form in their body fluids, like saliva, tears, gastric juice, etc.

The “A” and “B” substances are derived from the “H” substance

Blood Typing Using Saliva
blood typing using saliva1

If cells do not clump, the person is a secretor

If the cells clump (agglutination), the person is a non-secretor

Lectin is a plant substance that reacts with blood group substances

The lectin will indicate if an H substance is present in the blood (an H substance is the A or B)

Blood Typing Using saliva
blood detection labs

Before blood can be used as evidence, it must first be confirmed to be blood.

Test 1: Presumptive Blood test. This test shows the presence of hemoglobin. It is not human specific.

“Every contact leaves a trace.”

Blood evidence is extremely important in forensics. It can be used to determine the nature of the crime, blood types, DNA, recreate a crime scene, etc.

Blood detection labs
presumptive blood test

However, running blood tests and DNA tests is very time consuming and expensive. If a sample is sent to a lab for processing, it is best to know if the sample is most likely blood or not.

A presumptive blood test “presumes” a substance is blood if it reacts to chemicals in a particular way.

The most common presumptive test that is run is the Kastle-Meyer Test .

Presumptive blood Test
kastle meyer test

Kastle-Meyer is quick, inexpensive, easy and does not compromise the integrity of the sample, like DNA. It is very sensitive, 1:10,000. One drop of blood diluted 10,000 times with water can still be detected.

It does not distinguish between human and animal blood. It detects the iron in hemoglobin, so other products with iron could also give a positive result.

Kastle-meyer test
slide23

Products used: Alcohol (cleans sample and exposes more hemoglobin), phenolphthalein (changes color with oxidation – tells you if the test is bad and you need to redo it), hydrogen peroxide (releases extra oxygen, causes the pink color if oxygen is released from the hemoglobin)

blood detection labs1

Test 2: Luminol Test. This test shows where blood has been present but wiped away. It can also react to a number of substances such as copper or copper-containing alloys, and certain bleaches; and, as a result, if a crime scene is thoroughly cleaned with a bleach solution or horseradish, residual cleaner will cause the entire crime scene to produce the typical blue glow, effectively camouflaging any organic evidence, such as blood. Luminol reacts with fecal matter, causing the same glow as if it were blood.

Blood detection labs
slide25

Surface TensionThe elastic like property of the surface of the liquid that makes it tend to contract,caused by the forces of attraction between the molecules of the liquid.The cohesive forces tend to resist penetration and separation.

blood spatter

Bloodstain Pattern Analysis:is the examination of the shapes, locations, and distribution patterns of bloodstains, in order to provide an interpretation of the physical events which gave rise to their origin.

Based on the premise that all bloodstains and bloodstain patternsare characteristic of the forces that have created them.

blood spatter

FBI website

slide27

The determinations made from bloodstain patterns at the scene or from the clothingof principals in a case can be used to:

Confirm or refute assumptions concerning events and their sequence:Position of victim. (standing, sitting, lying)Evidence of a struggle. (blood smears, blood trails) n

Confirm or refute statements made by principals in the case:Are stain patterns on a suspects clothing consistent with his reported actions?Are stain patterns on a victim or at a scene consistent with accounts given by witnesses or the suspect?

FBI website

blood spatter1

At a crime scene the blood spatter patterns are photographed before the blood is collected so that the suspects account can be proved or disproven. The photographs will allow for an interpretation and reconstruction of what happened.

  • A. Size of blood splatter
    • 1. Recorded with micro scales visible in photographs.
    • 2. The smaller the drop the faster the movement of the blood.
Blood Spatter
blood spatter2

B. Shape of blood spatter

1. Recorded with micro scales visible in photographs.

2. Shape of the mark where it lands reveals the direction in which the drop was traveling and the amount of force it was projected with.

C. Directionality of blood spatter

1. The pattern that indicated the direction the blood was traveling when it hit the target surface.

2. Established from the geometric shape of the bloodstain.

Blood Spatter
blood spatter3

Velocity is the speed at which something travels with a direction.

    • A. Low-velocity impact spatter (LVIS)
      • 1. Caused by low-speed impact or force to a blood source.
      • 2. Velocity may be up to 5 feet per second or 1.5 meters per second.
      • 3. Drop size is larger than 3 millimeters.
Blood spatter
blood spatter4

B. Medium-velocity impact spatter (MVIS)

    • 1. Cause by medium-speed impact or force to a blood source.
      • a. Blunt force trauma, beating or a stabbing.
    • 2. Velocity is about 25 feet per second or 1.5-7.5 meters per second.
    • 3. Drop size or stain of 1-3 millimeters.
Blood SPATTER
blood spatter5

C. High-velocity impact spatter (HVIS)

    • 1. Caused by high-speed impact or force to a blood source.
      • a. Gunshot, explosive devices, a cough or sneeze.
    • 2. Velocity may be 100 feet per second or 30 meters per second.
    • 3. Drop size is a mist like appearance forming drops <1 millimeter.
Blood spatter
blood spatter patterns passive

Passive Bloodstains are drops created or formed by the force of gravity acting alone.

Drops, drip patterns, pools, clots

Drip pattern: A blood stain pattern that results from blood dripping into blood.

Blood Spatter Patterns: Passive
blood spatter patterns transfer

A transfer bloodstain is created when a wet, bloody surface comes in contact with a secondary surface.

Contact bleeding

Swipe or smear

Wipe

smudge

Blood Spatter Patterns: Transfer
blood stain patterns projected

Projected bloodstains are created when an exposed blood source is subjected to an action or force, greater than the force of gravity. (Internally or Externally produced)

Cast-off

Arterial spurt

Expirated

Blood Stain Patterns: Projected
blood spatter patterns summary

A. Drip pattern: A blood stain pattern that results from blood dripping into blood.

  • B. Cast-off pattern: A blood stain pattern created when blood is released or thrown from a moving a blood bearing object.
  • C. Transfer or Contact pattern: A blood stain pattern created when a wet, bloody surface comes in contact with a second surface.
  • Swipe pattern: The transfer of blood from a moving source into an unstained surface; the direction of travel may be determined by the feathered edges.
  • Spurt pattern: artierial spurts, appear as lines of blood
  • Expirated pattern: Blood that is blown out of the nose, mouth, or a wound as a result of air flow, which is the propelling force.
Blood spatter patterns Summary
blood spatter vocab cards

IN the Forensics book, pages 231-232, there are 35 blood spatter terms. Create flashcards for each term.

For the terms which describe how blood spatter looks, create a picture image of what it looks like using water color paints- so your flashcards for the following terms will have a word, a definition and a painted picture example

Blood Spatter Vocab Cards
blood spatter vocab cards1

The following terms need to have a painted picture: arterial spurting, bloodstain, cast-off pattern, contact stain, drip pattern, expirated blood, flow pattern, HVIS, impact pattern, LVIS, MVIS, misting, parent drop, passive drip, satellite spatter, spatter, spine, swipe pattern, transfer pattern, void, wipe pattern.

For HVIS, MVIS, LVIS, simple put a “drop” mark with the brush that is the right size in diameter.

Blood spatter vocab cards
directionality of blood spatter

When a droplet of blood strikes a surface perpendicular (90 degrees) the resulting bloodstain will be circular.That being the length and width of the stain will be equal.

Blood that strikes a surface at an angle less than 90 degrees will be elongated or have a tear drop shape.Directionality is usually obvious as the pointed end of the bloodstain ( tail ) will alwayspoint in the direction of travel.

Directionality of blood spatter
impact angle determination

ANGLE of IMPACTis the acute angle formed between the direction of the blood dropand the plane of the surface it strikes

iMpact Angle Determination
slide46

By utilizing trigonometric functions its possible to determine the impact angle for any given blood droplet.

SIN 0 = opp (a)

hyp (c)

slide48

SIN < = Width (a) 1.5cm

Length (c) 3.0cm

Width (a) 1.5cm = SIN <

Length (c) 3.0cm

0.5 = SIN <

< = 30 degrees

point of convergence and origin determination

The common point, on a 2 dimensional surface, over which the directionalityof several bloodstains can be retraced.

Once the directionality of a group of stains has been determined,it\'s possible to determine a two dimensional point or area for the group of stains.

POINT OF CONVERGENCE AND ORIGIN DETERMINATION
crime scene anaylsis of blood spatter

http://www.bloodspatter.com/cases.htm

Answer the questions the police would ask you.

Give an explanation of events for each picture

Crime scene anaylsis of blood spatter
collecting blood stain evidence

B. Dry blood stain collection

    • 1. Moisten sterile cotton-tip with sterile water.
    • 2. Rub over the blood stain until blood is picked up.
    • 3. Allow cotton swab to air dry.
    • 4. Package in a clean paper or envelope.
    • 5. Seal package with tamper resistant tape.
    • 6. Label with exhibit number, initials and date.
  • Or
    • 1. Tape-lift the bloodstain, scrape bloodstain into paper packet or cut the portion of the stain from the object it is on.
    • 2. Package in a clean paper or envelope.
    • 3. Seal package with tamper resistant tape.
    • 4. Label with exhibit number, initials and date.
Collecting blood stain evidence
collecting blood stain evidence1

C. Large object blood stain collection

    • 1. Cut out the blood stained areas.
    • 2. Allow for it to air dry.
    • 3. Package in paper bags or paper wrapping.
    • 4. Seal package with tamper resistant tape.
    • 5. Label with exhibit number, initials and date.
Collecting blood stain evidence
blood tests to identify blood products

A. Luminol- Used if a high-intensity light beam does not reveal blood at a crime scene after it has been cleaned.

    • 1. Luminol is a reagent that makes blood identifiable.
    • 2. Luminol is sprayed in a dark room to reveal drops of blood.
    • 3. Turns a fluorescent blue glow when it comes in contact with blood.
    • 4. Reacts with the iron that is found in the hemoglobin of blood.
    • 5. Glow will last 30 seconds and must be documented with a photograph.
    • 6. False positive can occur with metals, bleach and some plaster on walls.
BLOOD TESTS TO IDENTIFY BLOOD PRODUCTS
blood tests to identify blood products1

B. Hydrogen peroxide- A strong oxidizing agent.

    • 1. The heme in hemoglobin of RBC breaks down the peroxide.
    • 2. This reaction caused the production of oxygen that causes the stain to turn blue in color.
    • 3. Often hydrogen peroxide is used with the Kastle- Meyer Test.
  • C. Kastle- Meyer Test (K-M Test)- A blood test that uses the chemical indicator called phenolphthalein to detect the presence of hemoglobin.
    • 1. A blood sample is collected on a cotton-tipped swab and a drop of phenolphthalein is added to the tip.
    • 2. After a few seconds hydrogen peroxide is applied to the swab.
    • 3. If the swab turns bright pink rapidly it is positive for blood.
    • 4. After 30 seconds the swab will naturally turn pink as it oxidizes on its own in the air.
Blood tests to identify blood products
semen

Semen and saliva are other body fluids which are commonly found at crime scenes.

We will be examining semen from a bull. First, examine the live sperm in the microscope. Draw and describe what you see. How would a sperm count be made? How could a sperm count play a role in being evidence? (class or individual)

Using black light, examine the fabric to see if body fluid is present (in this case, bull semen). Describe the methods you used. Describe what you see.

How would this evidence be collected and sent back to the lab?

Semen
careers in blood

A. Phlebotomist

  • Collects blood samples by venipuncture.
    • 1. Level of education: High school diploma and accredited training program licensure.
    • 2. Credentialing requirements: Each state decided licensing.
    • 3. Employment opportunities and career growth potential: High demand.
    • 4. Workplace environments: Hospital, laboratory, clinics, and doctors office.
    • 5. Salary: $12.00/hour
Careers in blood
careers in blood1

B. Forensic Serology DNA Criminalist

  • Tests blood and other body fluids found at a crime scene.
    • 1. Level of education: Minimum of a Bachelors degree; often a Masters degree or Doctoral degree.
    • 2. Credentialing requirements: None.
    • 3. Employment opportunities and career growth potential: Good in current job market.
    • 4. Workplace environments: Law enforcement agencies, crime labs, Military agencies and medical professional agencies.
    • 5. Salary: $32,000 year/ average
Careers in blood
careers in blood2

Serology Technician

  • Work in the collection, testing, and analysis of evidence from a crime scene.
    • 1. Level of education: Minimum of an Associate’s degree; often a Bachelors degree or Masters degree.
    • 2. Credentialing requirements: Must go through a state/national accreditation training program.
    • 3. Employment opportunities and career growth potential: Good in current job market.
    • 4. Workplace environments: Law enforcement agencies, crime labs, government agencies and laboratories.
    • 5. Salary: $50,000 year/ average
Careers in blood
the case of lois mcarthur

This simulated crime scene will require you to use your knowledge of hair, fiber, trace and blood evidence to solve.

The Case of loismcarthur
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