Blood Spatter Analysis

Flashcards covering key vocabulary and concepts related to blood spatter analysis.

What causes blood flow?

Gravity

What must you measure of a droplet of blood to calculate the angle of impact?

Width and length

How does the distance of blood source from its target surface affect its appearance?

Higher the distance the larger the diameter, until 7 feet

How would you collect a pool of blood?

Soak up with a gauze pad, let it air dry and refrigerate, in a paper bag

When collecting blood what must be done?

Get blood to a lab within 48 hours, paper bag, air dry

little tiny droplets that are flung from the main drop are called?

Satellites

Above what height is the impossible to determine the height of a vertical drop

7ft

How many liters of blood are in an average adult?

5 liters to 5.5 liters

What is agglutilogens?

Antigens on red blood cells

What do white blood cells do?

Protect the body from infections

What are specialized proteins that aid in destroying infectious agents called?

Antibodies

What determines the type of blood

Antigens

What are the antibodies for blood type A

B

What blood type can donate to all others?

O-

What does plasma consist of?

Water, minerals, nutrients, sugar, red and white blood cells, and Platelets

Platelets are known as?

Thrombocytes

What do Platelets do?

They clump together to form a blood clot

Horizontal lines can be drawn to meet at one common area (point) called?

POC ( point of convergence)

A blood droplet will stay intact when falling through the air because of blood’s

High surface tension

Analysis of spatter patterns can help determine what?

Direction blood traveled, angle of impact, point of contact, velocity, manner of death

When blood travels through the air it is in what geometrical shape?

Spherical

Mostly linear streaks of blood that surround the outer edge of a patent drop are called

Spines

When a person is shot a close range the bloodstain on the shooters hand would be considered

Back spatter

What is used to detect minute amounts of blood in low light?

Luminol

name two presumptive tests

Kastle-Meyer test and Luminol

What color does the Q-tip turn if blood is present during the Kastle-Meyer test?

Pink

How long does a Lunimol test last?

30 seconds

Does luminol make DNA evidence unusable?

True ( yes )

What does the ELSIA test measure in the blood

Antibodies

Which test is confirmatory

The ELSIA test

What is the difference between presumptive and confirmatory tests?

presumptive establishes a possibility that a biological material is present, confirmatory is able to identify specific biological material.

What direction is the blood traveling

Left to right

What is the universal donor blood type

AB+

What blood stain pattern is this

Wipe

What caused this blood stain pattern

Arterial spur

What was the weapon used to produce this spatter

A blunt object

The first step in calculating the angle of impact AOI is

Measuring the length and width

As the angle that a blood droplet is dropped decreases the length…

Increase

What cause this blood stain

cast off

What type of spatter pattern is shown

Splash