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Contact Traces: Blood. Contact Traces: Blood. Serology: The study of blood and other liquids in forensics. Taking a sample of blood off the car windscreen. What is Blood?. Makes up 9% of a person’s body weight. T he average adult has about 5 to 6 litres of blood in their body.
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Contact Traces: Blood • Serology: The study of blood and other liquids in forensics. Taking a sample of blood off the car windscreen
What is Blood? • Makes up 9% of a person’s body weight. • The average adult has about 5 to 6 litres of blood in their body.
Blood and Crime • Common evidence in violent crimes What kind of violence would lead to blood traces? http://www.staffs.ac.uk/schools/sciences/forensic/forensicfacilities/photography.jpg
Blood and Crime • Difficult to remove from a crime scene which makes it very incriminating evidence
Blood and Crime • Tests for blood are so sensitive that they can show up blood that isn’t visible to the eye. A trail of latent blood made visible with the use of a reagent called luminol
Blood Groups • Discovered by Karl Lansteiner in 1901. • Four blood groups How is this useful in forensic science?
Blood Groups • Percentage of ABO blood group types in Australia
Blood Groups • Further categorized based on another antigen discovered by Dr Landsteiner in 1927.
Blood Groups • Blood groups are inherited from your parents • Only the dominant group is expressed
Blood Spatter: Prac this week • Examination of blood splashes and smears at a crime scene tell a story (click below for video)
Blood splatter analysis Dexter (click below for video)exterDe
Bloodstain patterns • Passive Bloodstains are caused by the force of gravity
Bloodstain patterns • Projected Bloodstains occur when some sort of energy or force has been transferred to the blood source.
Bloodstain patterns • Transfer/Contact bloodstains occur when a bloody object comes into contact with another object.
Blood splatter analysis • http://www.youtube.com/watch?v=2UV_moaF45I