Forensics Blood Analysis Unit Study Guide

Vocabulary Matching For each vocabulary term, match up the correct definition AND an example. Leukocytes White Blood Cells Plasma The fluid portion of blood obtained by centrifuging a sample of whole blood Agglutinate An allergic reaction where red blood cells clump together, usually in response to a particular antibody Erythrocytes Red Blood Cells Serology The study of body fluids using specific antigens and serum antibody reactions When a forensic scientist uses specific antigens and serum (antibody) they are performing this. Hemoglobin The oxygen carrier that gives red blood cells their color My job: I carry oxygen from lungs to body cells, then carry CO2 back to the lungs for removal Antigens Foreign substances in the body that are capable of causing disease Antibody A protein produced by a body’s immune system that tags molecules in order to destroy them Bloodstains Evidence that liquid blood has come into contact with a surface Main types: Passive, projected and transfer Blood Spatter Patterns produced under different conditions as a result of various forces applied to the source of blood Blood Cells I can differentiate between the blood cells in terms of structure and function. Fill in the table below. Erythrocyte Leukocyte Red Blood Cell White Blood Cell Platelet 1 3 2 no yes Transport O2 & CO2 Immunity Clotting Blood Cells Label the following blood sample using the following answer bank: Red Blood Cell, White Blood Cell, Platelet Platelet Red Blood Cell White Blood Cell True or False: A positive presumptive blood test result will give you 100% certainty that the sample you are testing is blood. True False Which of the following would be considered a presumptive blood test? ABO Blood Typing Test Angle of Impact Calculations Viewing Blood Sample Under a Microscope Luminol Test Which of the following would be the results of a positive luminol test? the sample would glow a bluish light when luminol is placed in the sample no color or light change would occur when luminol is added to the sample agglutination would occur when the luminol is added to the blood type that matches the luminol the luminol makes the blood drops more visible so its easier to measure the size of the blood drops and determine the speed of impact of the projected blood What component of blood will react with luminol in a positive test? Nitrogen Oxygen Iron Bleach Water Carbon Dioxide Passive, Projected Transfer Blood Stains Fill in the table below with the correct information. Type of Bloodstain Passive Pattern Projected Transfer Cast-Off Diagram Definition drop(s) of blood created by the force of gravity alone drops(s) of blood created when force is added to blood Created when a wet, bloody surface comes in contact with a second surface Created when blood is released or thrown from a moving blood-bearing object Example Dripping wound, blood pool o Arterial spurting (gushing) o Cast-of Wipe or swipe weapon or limb in a back swing Which of the following blood stains represents a wipe pattern? Which of the following describes a swipe blood stain pattern? original drops of blood can be seen and the blood has been smeared no original drops of blood can be seen, a surface wet with blood came into contact with a clean surface Labeling Blood Drops In the following diagram, label to parent, spine and satellite. satellite spine parent Low high velocity spatter Complete the table below. Categories AVE SIZE BLOOD DROPS SPEED OF BLOOD EXAMPLE OF CAUSE PICTURE EXAMPLES HIGH VELOCITY < 1 mm 100 ft gunshot LOW VELOCITY 4-8 mm 5 ft dripping wound MEDIUM VELOCITY 1-4 mm 5-25 ft stabbing or blow on the head As the angle of impact increases (going from 0 --> 90), the length of the resulting blood drop increases decreases Which angle of impact will result in a blood drop with a tail? 90 75 45 30 Projected blood On the following blood drop, label the parent and tail. Tail Parent Examine the diagram blow. Using the diagram and measuring tools in the diagram, calculate the angle of impact for this blood drop. Round your answer to the nearest whole number. The parent drop is about 1.3 mm tall and 2.6 mm long with a tail 1.4mm long. Which blood drop indicates that the original blood struck the surface in the direction of left to right? Area of Convergence Using the blood drops in the diagram below, Draw lines through the blood drops and circle the area of convergence of these drops. Blood Drops From Higher Height more satellites uneven border more spines Blood Drops from lower Height less satellites round border less spines How many injuries probably occurred in the scene above? 1 2 4 7 Blood types are determined by the presence of protein located on all of the blood cells only the white blood cells only on the T-helper cells only on the red blood cells What type of evidence is blood type? (Select all that apply) Individual Class Biological Eyewitness Physical Testimonial Pattern A Antigens Antibodies In the diagram below, type "yes" if present and "no" if not present in the blood types listed. yes no no no no no yes no no yes no yes yes no yes yes B Antigens and Antibodies In the diagram below, type in "yes" if present and "no" if not present. no yes yes no yes no no yes no yes yes no yes no no yes Rh Antigens Antibodies In the diagram below, type in "yes" if present and "no" if not present. yes no no yes yes no no yes yes no no yes no yes yes no What type of blood type is considered the universal donor? A+ B- AB+ AB- O+ O- What blood type is considered the universal recipient? AB+ AB- O+ O- A- B+ Based on the precipitation test above what is the blood type? AB- AB+ O+ O- B+ A- Based on the precipitation test above, what is the blood type? AB+ AB- O- O+ B- A+ Answer the questions below by using Reference Table B and Reference Table E. Round your answers to the nearest whole number. The percentage of population that would have A blood is 42 %.The percentage of the population that would have O- blood is 7 %The percentage of the population that would have AB+ blood is 3 %Secretors are 80 % of the population and their antigens are in other body fluids. Why do mothers have to be aware of the Rh factor? If the mother is Rh negative and her child is Rh positive she will form antibodies that may kill her second child (if they are also Rh positive) because of agglutination between the antibodies of the mother and the blood of the baby. To determine one’s blood type, what is added to the slide? (think about how it clumps together) blood and antibodies only the antibodies luminol none of the above Match the Type of Blood to What Can be Given for a Transfusion Write yes or no Categories Can Get A Can Get B Can Get O Can Get AB Type A Yes No Yes No Type B No Yes Yes No Type O No No Yes No Type AB Yes Yes Yes Yes