FORENSIC SCIENCE Serology Day Four

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FORENSIC SCIENCESerologyDay Four
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Todays assignments

• Killing Room Video Organizer
• Complete Serology Unit Quiz 1
• Then complete and turn in the Bloodstain pattern
  Technology assignment (on computer cart)

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Websites to use for Blood pattern technology
assignment

• http//www.bloodspatter.com/bloodstain-tutorial
• http//science.howstuffworks.com/bloodstain-patter
  n-analysis2.htm
• http//projects.nfstc.org/gallery/main.php?g2_item
  Id3857
• http//dsc.discovery.com/life/csi-knowledge-how-bl
  oodstain-pattern-analysis-works-infographic.html

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Forensic Files 5
Theres been a possible mixup at the
hospital! Baby 1 (with A blood type)has been sent
home with Mr. Mrs. Artery who both have A blood
type. Mr. Mrs. Vein (Mr AB Mrs AB) have been
sent home with Baby 2 who has O blood type.
Which baby belongs to which couple??? Prove with
Punnett
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Bloodstain Terminology

• Angle of impact--angle at which blood strikes a
  target surface.
• Bloodstain transfer--When a bloody object comes
  into contact with a surface and leaves a
  patterned blood image on the surface.
• Backspatter--blood that is directed back toward
  its source of energy.
• Cast-off--blood that is thrown from an object in
  motion

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Bloodstain Terminology

• Contact stain--general term referring to
  bloodstains caused by contact between a wet,
  blood-bearing surface and a second surface which
  may or may not have blood on it
• Transfer--image is recognizable and may be
  identifiable with a particular object
• Swipe--wet blood is transferred to a surface
  which did not first have blood on it
• Wipe--a non-blood bearing object moves through a
  wet bloodstain, altering the appearance of the
  original stain

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Bloodstain Terminology

• Directionality--relates to the direction a drop
  of blood traveled in space from its point of
  origin
• Terminal velocity--the greatest speed to which a
  free falling drop of blood can accelerate in air.
  It is dependent upon the acceleration of gravity
  and the friction of the air against the
  blood--approximately 251 feet/second.
• High velocity--greater than 100 feet per second
  gives a fine mist appearance
• Low velocity--5 feet per second or less
• Medium velocity--5 to 25 feet per second.