Forensic

Angle of Impact

The acute angle formed between the direction of a blood drop and the plane of the surface it strikes.

Arterial Spurting

Bloodstain pattern resulting from blood exiting the body under pressure from a breached artery

Back Spatter

blood directed back toward the source of energy or force that caused the spatter

Blood Spatter Analysis

A field of forensic science that deals with the physical properties of blood and the patterns produced under different conditions as a result of carious forces applied to the source of blood

Bloodstain

Evidence that liquid blood has come into contact with a surface

Cast-Off Pattern

A blood pattern created when blood is released or thrown from a moving blood-bearing object

Contact Stain

Blood deposited from direct contact between two surfaces at least one of which is bloody

Drip pattern

A bloodstrain pattern that results from blood dripping into blood.

Expirated Blood

Blood that is blown out of the nose, mouth, or a wound as a result of air pressure or air flow, which is the propelling force.

Flow Pattern

A change in the shape and direction of a blood stain due to the influence of gravity or movement of the object.

Forward Spatter

Blood that travels in the same direction as the source of energy or force that caused the spatter.

High - Velocity Impact Spatter

A bloodstain pattern caused by a high speed impact or force to a blood source such as that produced by gunshot, velocity may be 100 ft/sec, generally forming drops less than 1 mm.

satellite spatter

small droplets of blood distributed around a drop or pool of blood as a result of the blood hitting the target surface

Area of Origin

The place from where the blood spatter came from or originated

Blood spatter spines

pointed edges of a stain that radiate out from the spatter; can help determine the direction from which the blood traveled.

Plasma

Fluid portion of blood

Erythrocytes

red blood cells

Leucocytes

white blood cells

Passive drop

blood drop created solely as a result of gravity

Cohesion

Attraction between molecules of the same substance

Antigens

Proteins found on the surface of red blood cells- acts like a chemical name tag

Kastle-Meyer test

a chemical test to determine if a stain is blood

Precipitin Test

test that distinguishes between human and animal blood

Luminol

A chemical that emits a blue glow when it comes in contact with blood

Serology

The study of reactions between antibodies and antigens and serum

lines of convergence

found by drawing straight lines down the long axis of blood spatter and noting where they intersect

Agglutination

Clumping that occurs when blood antibodies combine with their matching antigen

Void Pattern

absence of blood spatters in an area where you'd other wise expect to see them; indicated where attacker stood

impact spatter

occur with beatings, stabbings, gunshots, or when a foreign object impacts a victim

ABO blood groups

based on having an A, B, both or no antigens on red blood cells

Rh factor

presence or lack of antigens on the surface of red blood cells, which causes a reaction between Rh-positive blood and Rh-negative blood

Transfer Blood stains

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

Projected Bloodstains

patterns from when a force is applied to the source of the blood includes low, medium or high impact spatters, cast-off, arterial spurting, expiratory blood blown out of the nose, mouth or wound