Studied by 4 peopleblood typing
= class evidence
DNA profiling
= individual evidence
cells are present in __ % in blood
45%
different kinds of cells
red blood cells, white blood cells and platelets
plasma is present in __ % in blood
55%
plasma is __ % water
90%
plasma contains
dissolved proteins, O2, wastes, nutrients
serum can
determine the freshness of a blood sample
forensic serology
determination of the type and characteristics of blood
blood is the most common and most important piece of
evidence
bloodstain patterns tell a lot about
position and movement during the crime
blood is a slightly
alkaline fluid made up of water, cells and proteins
no 2 individuals except for identical twins can be expected to have the same combination of
blood types or antigens
red blood cells transport
oxygen from the lungs to the body tissues and carry carbon dioxide back to the lungs
on the surface of the red blood cells are chemical substances called
antigens
an antibody will react with only
a specific antigen
agglutination is the clumping together of red blood cells by the action of
an antibody
the term serology
describes the study of all body fluids
luminol
reagent reacts with blood causing it to luminesce
blood can be characterized as being of human origin by the
percipin test
approx. 80% of the population is classified as
secretors
O
people with type __ blood are called universal donors because they can give blood to anyone
hemoglobin
protein found in red blood cells that carries oxygen
lcv
test used at a crime scene to enhance a bloodstain to make it more visible in photographs
passive
type of blood stain created by the force of gravity and appears as drops or blood pools
platelets
clot together to prevent blood loss from a wound
projected
bloodstain that is created when a force is applied to the source of the blood
AB
people with type _____ blood are called universal recievers because they can receive from anyone
red blood cells are the
most abundant cells in our body that are produced in the bone marrow
rh factor
indicated the presence of a specific protein; discovered while studying the rhesus monkeys
spatter
bloodstains created by the application of force to the area where the blood is orginated
spines
pointed edges of a droplet that radiate out from the spatter and can help to determine the direction of force
transfer
patterns created when a bloody object comes in contact with another surface; also called contact patterns
type A
blood type that contains A agglutinogens
agglutinogens
an antigen that stimulates the production of an agglutinin
an antibody, lectin, or other substance that causes agglutination
agglutinin
type AB
blood type that contains both A and B agglutinogens
type B
blood type that contains B agglutinogens
type O
blood type that does not contain A or B agglutinogens
white blood cells
Component of blood that is part of our immune system and destroy pathogens in our body
if you find a trail of blood with droplets that are very close together what could this mean
it could possibly be that the person who was bleeding was moving very slowly
spatter
bloodstains created from the application of force to the area where the blood originated
origin
the place from where the blood spatter came from
angle of impact
the angle at which a blood droplet strikes a surface
parent drop
the droplet from which a satellite spatter orginates
satellite
small drops of blood that breaks off from the parent spatter when the blood droplet hits a surface
this type of pattern is described as being created from the force of gravity
passive
projected patterns create
patterns that occur when a force is applied to the source of the blood
transfer
the pattern created when a wet bloody object comes in contact with a target source
projected
the bloody footprint found on the scene
passive
this is the type of blood stain that results from a gun shot wound
transfer
the blood stain that results from blood blown out of the nose
the type of blood stain that would be found on clothing
transfer
lcd
test used at a crime scene to enhance a bloodstain to make it more visable in photographs
erythrocyte
is a red blood cell that (in humans)
red blood cells do not have
a nucleus
leukocyte
a white blood cell
a white blood cell has
a nucleus
if blood clumps, proteins are
present
serology
the examination and analysis of body fluids
presumptive tests
analyses a sample to determine if a substance is or is not a substance
one type of a presumptive test
kastle meyer
kastle meyer color test
a mix of phenolphtalein and hydrogen peroxide
luminol test
reaction with blood to produce blue light
blue light
luminescence
in the kastle meyer test:
the hemoglobin will cause the ofrmation of a deep pink if blood is present
another type of presumptive test for blood is called
luminol test
a kind of test to determine if blood is human at a crime scene
microscopic examination
another kind of test to determine if blood is human at a crime scene
precipitin test
precipitin test
blood is injected into
animals blood has larger red blood cells with a
nucleus
cohesion
blood sticks together as it falls
gravity
pulls blood downward
surface tension
blood drops that fall on a flat surface have a curved surface
edges may have spikes or
extentions
satellites
small secondary droplets
how many different kinds of blood spatter are there
6 different types
passive fall
90 degree angle to the floor
passive fall will cause ____ drops
perfect circular drops
arterial spurts or gushes
when u cut an artery
splashes
show position of victim
smears
bleeding victim touching walls or furniture
blood trails
victim moving from one place to another
blood pools
victim bleed heavily
cast off pattern
blood from a moving object coated in blodo
cast off pattern could be from
a pipe or a knife
fine mist spatter
high velocity impact
fine mist spatter could be from
a gunshot
void
empty space
secondary spatter
upward splash of blood from a drip
medium velocity examples
beating or stabbing
pointed end of stain faces its
direction of travel
degree of circular distortion tells us the angel of
blood projection
to confirm the stain is human
enzyme-linked immunoassay
to determine the blood type do
the antibody test
round shape of blood drop
if it falls down straight at a 90 degree angle
elliptical shape of a blood drop
blood droplets elongate as the angle decreases from 90 to 0 degrees
lines of convergence
determines the source of blood (point of origin)
Note
Flashcard