1. Biological sciences have made huge advancements in our understanding of the functions of blood. Forensics relies on this knowledge to assist in determining individual identities; it also uses the physical evidence of blood found at crime scenes to assist in reconstructing the events of crimes.

2. Historical methods of identifying and individualizing blood and other body fluids Antigen-Antibody reactions Enzyme-Substrate reactions Forensic Serology

3. HISTORY In 1901 Dr. Karl Landsteiner discovered blood typing. awarded a Noble Prize.

4. White blood cells Platelets Red blood cells Artery

5. Plasma- 55% Formed elements- 45% Buffy coat- <1%

6. ANTIGENS

7. a a a a a a a a b b b b b b b b

8. AGGLUTINATION

9. Figure 17.16 Serum Anti-A RBCs Anti-B Type AB(contains agglutinogens A and B; agglutinates with both sera) Blood being tested Type A(contains agglutinogen A; agglutinates with anti-A) Type B(contains agglutinogen B; agglutinates with anti-B) Type O(contains no agglutinogens; does not agglutinate with either serum)

10. Can this blood be associated to a particular individual? MAYBE!?!

11. Blood Type & RhHow Many Have ItFrequency ORh Positive1 person in 337.4% ORh Negative1 person in 156.6% ARh Positive1 person in 335.7% ARh Negative1 person in 166.3% BRh Positive1 person in 128.5% BRh Negative1 person in 671.5% ABRh Positive1 person in 293.4% ABRh Negative1 person in 167.6%