BLOOD COMPOSITION AND FUNCTION HTTP://YOUTU.BE/UQP3XM3ZUGI BLOOD AND BLOOD SPATTER BY THE END OF THIS CHAPTER YOU WILL BE ABLE TO: EXPLAIN THE COMPOSITION OF BLOOD DESCRIBE THE FUNCTION OF BLOOD CELLS DETERMINE THE BLOOD TYPE OF A BLOOD SAMPLE
CONDUCT A BLOOD SPATTER ANALYSIS EXAMINE WOUNDS AND DESCRIBE THE NATURE OF THE WEAPON FIND AND PROCESS BLOOD EVIDENCE 2 CRIME SCENE INVESTIGATION OF BLOOD 1. SEARCH FOR BLOOD EVIDENCE 2. DETERMINE a. IS THE EVIDENCE BLOOD? b. IS THE BLOOD HUMAN?
c. WHAT IS THE BLOOD TYPE? 3. INTERPRET THE FINDINGS: a. DOES THE BLOOD TYPE MATCH A SUSPECTS BLOOD? b. IF NOT, EXCLUDE THAT SUSPECT c. IF YES, DECIDE IF DNA PROFILING IS NECESSARY 3 INTRODUCTION AND HISTORY BLOOD TYPING PROVIDES CLASS EVIDENCE
DNA PROFILING PROVIDES INDIVIDUAL EVIDENCE A BLOOD SPLATTER PATTERN PROVIDES INFORMATION THE TRUTHFULNESS OF AN ACCOUNT BY A WITNESS
OR A SUSPECT THE ORIGIN OF THE BLOOD THE ANGLE AND VELOCITY OF IMPACT THE TYPE OF WEAPON USED
4 COMPOSITION OF BLOOD PLASMAA LIQUID SUSPENDING OTHER BLOOD COMPONENTS RED BLOOD CELLS (ERTHROCYTES)CARRIES OXYGEN TO THE BODYS CELLS AND CARBON DIOXIDE AWAY WHITE BLOOD CELLS (LEUKOCYTES)FIGHTS DISEASE AND FOREIGN INVADERS AND,
ALONE, CONTAIN CELL NUCLEI PLATELETSAIDS IN BLOOD CLOTTING AND THE REPAIR OF DAMAGED BLOOD VESSELS 5 COMPOSITION OF BLOOD 6 TYPES OF WHITE BLOOD CELLS Type of WBC
% in blood Role Neutrophil 40-70% Phagocytizes bacteria Eosinophil
1-4% Phagocytizes and destroys antigenantibody complexes Basophil 0-1% Releases histamine when stimulated Lymphocyte
20-45% B-produces antibodies in blood/lymph T-kills virus-containing cells Monocyte 4-8% Becomes macrophage
(phagocytizes bacteria/viruses 7 CELLULAR COMPONENTS OF BLOOD 8 Chromosomes: DNA wrapped around protein. It is condensed so it can be transferred to new cells.
Meiosis: forms unique gametes (sex cellssperm/ egg) Haploid (n): set of chromosomes, gamete (sex) cells Diploid (2n): full set of MEIOSIS SOME DEFINITIONS. GENETICS: THE SCIENTIFIC STUDY OF HEREDITY.
TRAIT: A SPECIFIC CHARACTERISTIC OF AN INDIVIDUAL. (FOR EXAMPLE??) GENE: SEQUENCE OF DNA THAT CODES FOR A PROTEIN (AND, THEREFORE, A TRAIT) PASSED DOWN FROM PARENT TO OFFSPRING ALLELE: DIFFERENT POSSIBLE FORMS OF A GENE (ONE FROM EACH PARENT) HOMOZYGOUS: 2 OF THE SAME ALLELE FOR THE SAME GENE PRINCIPLE OF DOMINANCE
DEFINITION: SOME ALLELES ARE DOMINANT AND OTHERS ARE RECESSIVE Which is the dominant allele for eye color, and which is the recessive? GENOTYPE VS. PHENOTYPE GENOTYPE: THE GENETIC MAKEUP (I.E. COMBINATION OF ALLELES FOR EACH PARTICULAR GENE) PHENOTYPE: THE PHYSICAL TRAITS EXHIBITED BY AN ORGANISM (OBSERVABLE) CAN WE PREDICT WHICH TRAIT(S) WILL BE
INHERITED?? PROBABILITY: DEFINITION?? PUNNETT SQUARES PUNNETT SQUARE PRACTICE IF A FATHER IS TYPE IAIA AND THE MOTHER IS IBIi, WHAT IS THE PROBABILITY OF THE OFFSPRING HAVING THE BLOOD TYPE IAIB? BLOOD TYPINGPROTEINS DISCOVERED IN 1900 BY KARL LANDSTEINER
IDENTIFIES THE PRESENCE OR ABSENCE OF PARTICULAR PROTEINS EMBEDDED IN THE CELL QUICKER AND LESS EXPENSIVE THAN DNA PROFILING PRODUCES CLASS EVIDENCE BUT CAN STILL LINK A
SUSPECT TO A CRIME SCENE OR EXCLUDE A SUSPECT 15 BLOOD TYPING ANTIGENS & ANTIBODIES BLOOD TYPINGPROTEINS 42% 12% 3% 43% of the population in the United States
17 RH FACTOR 85% OF THE POPULATION HAS A PROTEIN CALLED RH FACTOR ON THEIR BLOOD CELLS 18 RH FACTOR BLOOD TYPINGANTIBODIES ANTIBODIES ARE Y-SHAPED PROTEINS SECRETED BY WHITE
BLOOD CELLS THAT ATTACH TO ANTIGENS TO DESTROY THEM (IMMUNE RESPONSE) ANTIGENS (ANTIBODY GENERATOR) ARE CARBOHYDRATES ATTACHED TO THE SURFACE OF CELLS THAT REACT WITH ANTIBODIES 20 ANTIGEN/ANTIBODY RESPONSE IN THE PRESENCE OF FOREIGN ANTIGENS, ANTIBODIES BIND TO THE ANTIGEN AND, IN
THE CASE OF BLOOD, CAUSE AGGLUTINATION, (CLUMP TOGETHER). BLOOD TYPING PROBABILITY AND BLOOD TYPES THE PROBABILITY OF A BLOOD TYPE EQUALS THE PRODUCT OF PROBABILITIES FOR EACH PROTEIN GROUP IF TYPE A = 42% AND RH FACTOR = 85% THEN A+ = .42 X .85 = .357 (35.7%) KNOWING ADDITIONAL PROTEINS AND ENZYMES
IN THE BLOOD SAMPLE NARROWS THE POPULATION GROUP INCREASES THE PROBABILITY OF IDENTIFYING A SUSPECT 23 PRACTICE PROBLEM WHAT IS THE PROBABILITY OF HAVING ABBLOOD KNOWING AB IS 3% OF THE POPULATION, AND NO RH IS 15%? .03x.15=.0045x100=.45% of the population (rare!!!)
PRESUMPTIVE BLOOD STUFF BLOOD SPATTER AND ANALYSIS HTTP://YOUTU.BE/MLX3-1E1C8U INTRODUCTION AND HISTORY BLOOD TYPING PROVIDES CLASS EVIDENCE
DNA PROFILING PROVIDES INDIVIDUAL EVIDENCE A BLOOD SPLATTER PATTERN PROVIDES INFORMATION THE TRUTHFULNESS OF AN ACCOUNT BY A WITNESS OR A SUSPECT
THE ORIGIN OF THE BLOOD THE ANGLE AND VELOCITY OF IMPACT THE TYPE OF WEAPON USED 27
CRIME SCENE INVESTIGATION OF BLOOD 1. SEARCH FOR BLOOD EVIDENCE 2. DETERMINE a. IS THE EVIDENCE BLOOD? b. IS THE BLOOD HUMAN? c. WHAT IS THE BLOOD TYPE? 3. INTERPRET THE FINDINGS: a. DOES THE BLOOD TYPE MATCH A SUSPECTS BLOOD? b. IF NOT, EXCLUDE THAT SUSPECT c. IF YES, DECIDE IF DNA PROFILING IS NECESSARY
28 BLOOD SPATTER 1939SPATTER PATTERNS FIRST ANALYZED BLOOD MAY SPATTER WHEN A WOUND IS INFLICTED
BLOOD SPATTER PATTERNA GROUPING OF BLOOD STAINS PATTERNS HELP TO RECONSTRUCT THE EVENTS SURROUNDING A SHOOTING, STABBING, OR BEATING 29 BLOOD SPATTER ANALYSIS
ANALYSIS OF A SPATTER PATTERN CAN AID IN DETERMINING THE: DIRECTION BLOOD TRAVELED ANGLE OF IMPACT POINT OF ORIGIN OF THE BLOOD VELOCITY OF THE BLOOD MANNER OF DEATH 30 BLOOD SPATTER ANALYSIS NATURAL COHESIVENESS OF BLOOD
31 BLOOD SPATTER ANALYSIS SATELLITE DROPLETS WHEN BLOOD FALLS FROM A HEIGHT, OR AT A HIGH VELOCITY, IT OVERCOMES ITS NATURAL COHESIVENESS, AND SEPARATES FROM THE MAIN DROPLET SPIKING PATTERNS FORM AROUND THE DROPLET
EDGES WHEN BLOOD FALLS ONTO A LESS-THAN-SMOOTH SURFACE 32 BLOOD SPATTER ANALYSIS DIRECTIONALITY THE SHAPE OF AN INDIVIDUAL DROP OF BLOOD PROVIDES CLUES TO THE DIRECTION FROM WHERE THE BLOOD ORIGINATED.
HOW WILL THE POINT OF IMPACT COMPARE WITH THE REST OF A BLOOD PATTERN? 33 BLOOD SPATTER ANALYSIS Lines of convergencetwo or blood spatters can pinpoint the location of the blood source (forms area of convergence) 34 BLOOD SPATTER ANALYSIS
SIX PATTERNS DESCRIBE EACH OF THESE: a) PASSIVE DROPS b) ARTERIAL GUSHES c)
SPLASHES d) SMEARS e) TRAILS f) POOLS
35 BLOOD SPATTER ANALYSIS IMPACT PATTERNS CAN HELP INVESTIGATORS DETERMINE THE TYPE OF WEAPON USED WHAT KIND OF A PATTERN IS PRODUCED BY A GUN SHOT? WHAT KIND OF A PATTERN IS PRODUCED BY A HAMMER BLOW?
36 CRIME SCENE INVESTIGATION OF BLOOD 1. SEARCH FOR BLOOD EVIDENCE 2. DETERMINE a. IS THE EVIDENCE BLOOD? b. IS THE BLOOD HUMAN? c. WHAT IS THE BLOOD TYPE? 3. INTERPRET THE FINDINGS: a. DOES THE BLOOD TYPE MATCH A SUSPECTS BLOOD? b. IF NOT, EXCLUDE THAT SUSPECT
c. IF YES, DECIDE IF DNA PROFILING IS NECESSARY 37
