FIS 201 EXAM 3 WITH ALL CORRECT & VERIFIED
ANSWERS|ALREADY GRADED A+|JUST RELEASED
What are the requirement for a bloodstain pattern analyst? Correct answer--no formal education
requirements
-certification through IAI and American Criminalistics Society
What are the 4 phases of stain creation? Correct answer--contact/collapse
-displacement
-dispersion
-retraction
What is a bloodstain pattern? Correct answer-grouping or distribution of bloodstains that indicates
the manner in which the pattern was deposited
What two parts is blood compromised of? Correct answer--hematocrit
-plasma
What happens in the contact/collapse stage of impact? Correct answer-Blood droplet his the
object and collapses from the bottom up
What happens in the displacement stage of impact? Correct answer-slight dimples and spines
begin to form around the edge of the drop
What happens in the dispersion stage of impact? Correct answer-most of the volume of blood is
forced up and out so the spines are extended outward
What happens in the retraction stage of impact? Correct answer-surface tension pulls the drop flat
and the satellites with enough momentum break free
What is satellite spatter? Correct answer-small droplets of blood broken from the main drop
The size of a blood droplet is dependent on what? Correct answer-volume and velocity
What is low velocity spatter? Correct answer--spatter that is 3mm or greater in diameter
-this type of spatter is usually causes blood to fall under the influence of gravity
-usually forms from weapon cast-off, a person remaining still, walking, or running
What is medium velocity spatter? Correct answer--spatter the is 1-3mm in diameter
-usually forms from blunt force trauma, sharp trauma, or cast-off
What is high velocity spatter? Correct answer--spatter that is less than 1mm in diameter
-appears as a fine spray or misting
-usually forms from gunshot trauma, power tools, an object striking with extreme velocity, or an
explosion
What is impact/forward spatter? Correct answer-blood displaced by energetic impact
What is a cast-off pattern? Correct answer-when blood is released or thrown from a blood-bearing
object in motion
, What can you tell from cast-off? Correct answer--speed
-size of object
-number of swings
What is a projected pattern? Correct answer-when blood exits the body under pressure from a
breached artery
What is expirated blood? Correct answer-blood that is blown out of the mouth, nose, or a would. It
is often diluted or contains mucous.
What is the area of convergence? Correct answer-When you draw a straight line through the back
of blood stains and where the lines intersect is the area of convergence
How do you tell the direction of a blood stain? Correct answer-the tail (pointy part) tells which way
the bloodstain goes
What is a void? Correct answer-an absence of blood
What shows that the crime scene has not been disturbed? Correct answer--bubble rings
-drips
-saturation
What can show the order of things that happened at a crime scene? Correct answer--flow
-pattern transfer
-skeletonization
-swipes
-wipes
-insect artifact
What are bubble rings? Correct answer-when blood containing air bubbles dries (shows that the
blood is older and not disturbed)
What is a flow pattern? Correct answer-the motion of blood under gravity (if an object has been
moved then the flow pattern should look a little weird)
What is a drip pattern? Correct answer-when blood drips into other blood (there should be lots of
satellite spatter)
This shows that the crime scene has not been disturbed
What is a saturation stain? Correct answer-a large volume of absorbed blood
What is a wipe pattern? Correct answer-when an object moves through an existing stain
What is a swipe pattern? Correct answer-the transfer of blood from a dirty source onto a clean
source
What is a skeletonized stain? Correct answer-the pattern left when an object moves through a
partially dried stain, removing part of the blood, but leaving the outline of the stain intact
When is trace evidence formed? Correct answer-generated when objects touch each other and
remains of material are left behind
ANSWERS|ALREADY GRADED A+|JUST RELEASED
What are the requirement for a bloodstain pattern analyst? Correct answer--no formal education
requirements
-certification through IAI and American Criminalistics Society
What are the 4 phases of stain creation? Correct answer--contact/collapse
-displacement
-dispersion
-retraction
What is a bloodstain pattern? Correct answer-grouping or distribution of bloodstains that indicates
the manner in which the pattern was deposited
What two parts is blood compromised of? Correct answer--hematocrit
-plasma
What happens in the contact/collapse stage of impact? Correct answer-Blood droplet his the
object and collapses from the bottom up
What happens in the displacement stage of impact? Correct answer-slight dimples and spines
begin to form around the edge of the drop
What happens in the dispersion stage of impact? Correct answer-most of the volume of blood is
forced up and out so the spines are extended outward
What happens in the retraction stage of impact? Correct answer-surface tension pulls the drop flat
and the satellites with enough momentum break free
What is satellite spatter? Correct answer-small droplets of blood broken from the main drop
The size of a blood droplet is dependent on what? Correct answer-volume and velocity
What is low velocity spatter? Correct answer--spatter that is 3mm or greater in diameter
-this type of spatter is usually causes blood to fall under the influence of gravity
-usually forms from weapon cast-off, a person remaining still, walking, or running
What is medium velocity spatter? Correct answer--spatter the is 1-3mm in diameter
-usually forms from blunt force trauma, sharp trauma, or cast-off
What is high velocity spatter? Correct answer--spatter that is less than 1mm in diameter
-appears as a fine spray or misting
-usually forms from gunshot trauma, power tools, an object striking with extreme velocity, or an
explosion
What is impact/forward spatter? Correct answer-blood displaced by energetic impact
What is a cast-off pattern? Correct answer-when blood is released or thrown from a blood-bearing
object in motion
, What can you tell from cast-off? Correct answer--speed
-size of object
-number of swings
What is a projected pattern? Correct answer-when blood exits the body under pressure from a
breached artery
What is expirated blood? Correct answer-blood that is blown out of the mouth, nose, or a would. It
is often diluted or contains mucous.
What is the area of convergence? Correct answer-When you draw a straight line through the back
of blood stains and where the lines intersect is the area of convergence
How do you tell the direction of a blood stain? Correct answer-the tail (pointy part) tells which way
the bloodstain goes
What is a void? Correct answer-an absence of blood
What shows that the crime scene has not been disturbed? Correct answer--bubble rings
-drips
-saturation
What can show the order of things that happened at a crime scene? Correct answer--flow
-pattern transfer
-skeletonization
-swipes
-wipes
-insect artifact
What are bubble rings? Correct answer-when blood containing air bubbles dries (shows that the
blood is older and not disturbed)
What is a flow pattern? Correct answer-the motion of blood under gravity (if an object has been
moved then the flow pattern should look a little weird)
What is a drip pattern? Correct answer-when blood drips into other blood (there should be lots of
satellite spatter)
This shows that the crime scene has not been disturbed
What is a saturation stain? Correct answer-a large volume of absorbed blood
What is a wipe pattern? Correct answer-when an object moves through an existing stain
What is a swipe pattern? Correct answer-the transfer of blood from a dirty source onto a clean
source
What is a skeletonized stain? Correct answer-the pattern left when an object moves through a
partially dried stain, removing part of the blood, but leaving the outline of the stain intact
When is trace evidence formed? Correct answer-generated when objects touch each other and
remains of material are left behind
