1. Copyright © 2013 Crosscutting Concepts, LLC. All Rights Reserved. www.CrosscuttingConcepts.com Warm-Up November 17, 2014 What are some of the different type of blood stain patterns?

2. Copyright © 2013 Crosscutting Concepts, LLC. All Rights Reserved. www.CrosscuttingConcepts.com Objective SWBAT perform presumptive blood test to determine if blood is present.

3. Copyright © 2013 Crosscutting Concepts, LLC. All Rights Reserved. www.CrosscuttingConcepts.com Agenda 1.Crime 360 2.Blood Detection Pre-Lab 3.Blood Detection Overview 4.Detection Lab 1 5.Exit Slip

4. T. Trimpe 2008 http://sciencespot.net/ How Stuff Works Underwater Detectives

5. 1. What was the crime? A. A body was dumped in the water. B. A person fell over the side of a boat and drowned. C. A boat was stolen. 2. Why wasn’t the “killer” worried about leaving evidence behind? A. He knew the evidence couldn’t be traced back to him. B. He figured the water would wash away all the evidence. 3. True or False? Fingerprints are likely to remain on evidence found in the water. 4. What is the correct order for processing a water crime scene? A. Photograph the area, gather evidence, and record measurements B. Record measurements, photograph the area, and gather evidence C. Photograph the area, record measurements, and gather evidence Watch the video and then answer the questions. http://videos.howstuffworks.com/science-channel/14374-discoveries-this-week-underwater-detectives-video.htm

6. 1. What was the crime? A. A body was dumped in the water. B. A person fell over the side of a boat and drowned. C. A boat was stolen. 2. Why wasn’t the “killer” worried about leaving evidence behind? A. He knew the evidence couldn’t be traced back to him. B. He figured the water would wash away all the evidence. 3. True or False? Fingerprints are likely to remain on evidence found in the water. 4. What is the correct order for processing a water crime scene? A. Photograph the area, gather evidence, and record measurements B. Record measurements, photograph the area, and gather evidence C. Photograph the area, record measurements, and gather evidence The answers are …

7. Blood Spatter Labs You will be creating sample drop patterns using single drops and multiple drops. We will also investigate the effect of motion and the angle of impact on blood spatter. This can be messy! Be very careful to keep the blood on the paper and not on yourself, the table, or floor. Hold you hand as steady as possible when making the drops. Brace your wrist against the meter stick to help you. Get your materials from your teacher – paper, black marker, meter stick, goggles, and a bottle of blood. If you make a mess, clean it up immediately!

8. Lab 1: Single Droplets 2550 Single Drops Group Members 75100 Single Drops Group Members Label two large pieces of construction paper as shown below. To do the lab, put on your goggles and hold the dropper bottle upside down so that the end of it is 25 cm from the paper. GENTLY squeeze the bottle so that ONE drop of blood is released and lands in the correct location on your paper. It should NOT hit the meterstick. Repeat TWO more times at this height for a total of three drops. Continue making drops of blood on your paper, but put the drop in a different area of the paper and change the height each time. When you are done, analyze your results and answer the questions on your worksheet. Make a mistake? Use a paper towel to wipe it off your paper! Keep your drops in the correct area of the paper.

9. Use your results to answer these questions. What did you notice about the diameter of the parent droplets as you increased the height of the drop? How do the spines compare from the different heights? Lab 1 Questions

10. Lab 2: Multiple Droplets Label a long piece of butcher paper (2 -3 meters in length) as shown below. To do the lab, put on your goggles and hold the dropper bottle upside down so that the end of it is 25 cm from the paper. GENTLY squeeze the bottle so that ONE drop of blood is released and lands in the correct location on your paper. The drop should NOT hit the meterstick. Without moving your hand, release ONE more drop onto the first drop at that height. If you make a mistake, wipe it off with a paper towel and try it again. Continue making drops of blood on your paper so you have three sets for each height. When you are done, analyze your results and answer the questions on your worksheet. Clean up your area and put away your materials before you leave class. Multiple Drops Group Members 255075100 Keep your drops in the correct area of the paper.

11. Use your results to answer these questions. What happened when one drop landed on top of another one? What did you notice about the diameter of the parent droplets as you increased the height of the drop? What do you notice about the diameter of the satellite spatter as you increased the height of the drop? Lab 2 Questions

12. Lab 3: Motion Droplets During this lab, you will see how motion affects the size and shape of the droplets and spines. You will need a long piece of butcher paper (4-5 meters in length) and tape to secure it to the floor. You will also need safety goggles. To do the lab, you will need to hold the dropper bottle upside down so that your hand is out and away from your body (waist level), but is still over the paper. Start off walking at a SLOW WALKING RATE along the paper strip from one end to the other and GENTLY squeeze the bottle as you walk so that blood is released ONE DROP at a time. Be sure that all the drops land on your paper strip. Repeat this procedure using a NORMAL WALKING RATE and a FAST WALKING RATE. Walking Direction When you are done, analyze your results and answer the questions on your worksheet. Clean up your area and put away your materials before you leave class. Miss the paper? Use a paper towel to wipe it off the floor!

13. Use your results to answer these questions. Draw a sketch of the droplets showing the size, shape, and/or distance between them at each speed in the chart below. What did you notice about the shape of the droplets as you increased your walking speed? What did you notice about the spines as you increased your walking speed? What did you notice about the distance between the droplets as you increased your walking speed? Lab 3 Questions

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15. Copyright © 2013 Crosscutting Concepts, LLC. All Rights Reserved. www.CrosscuttingConcepts.com Pre Lab Questions Complete the Pre-Lab questions using the information that is posted on the wiki page

16. Copyright © 2013 Crosscutting Concepts, LLC. All Rights Reserved. www.CrosscuttingConcepts.com Blood Stain Evidence Blood is a type of biological evidence that can connect a suspect to a victim or object. White blood cells contain DNA which may be used to identify an individual from a blood sample. Lab testing can differentiate between human and animal blood by protein or DNA analysis.

17. Copyright © 2013 Crosscutting Concepts, LLC. All Rights Reserved. www.CrosscuttingConcepts.com Biological Properties of Blood Blood delivers nutrients and oxygen to the cells and transports waste products away from cells. Red blood cells carry oxygen and carbon dioxide.

18. Copyright © 2013 Crosscutting Concepts, LLC. All Rights Reserved. www.CrosscuttingConcepts.com Biological Properties of Blood White blood cells come in many varieties that fight off infection in different ways, such as by generating antibodies or breaking down intruder cells. They also contain DNA.

19. Copyright © 2013 Crosscutting Concepts, LLC. All Rights Reserved. www.CrosscuttingConcepts.com Biological Properties of Blood Platelets assist in clotting.

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21. Copyright © 2013 Crosscutting Concepts, LLC. All Rights Reserved. www.CrosscuttingConcepts.com Biological Properties of Blood Main elements used in forensic labs: –Red blood cells –Serum proteins Red blood cells have structures called antigens on their surfaces. They are grouped into classification systems determined by their relationship to one another (blood type).

22. Copyright © 2013 Crosscutting Concepts, LLC. All Rights Reserved. www.CrosscuttingConcepts.com Biological Properties of Blood Serum proteins such as antibodies are used to test the sample to confirm that it is blood. An antibody activates or destroys a specific antigen which allows for particular reactions to occur when specific groups of antigens and antibodies are mixed. These reactions allow for determination of blood type.

23. Copyright © 2013 Crosscutting Concepts, LLC. All Rights Reserved. www.CrosscuttingConcepts.com Biological Properties of Blood The ABO group system for blood typing was first used in the early 1970’s to link blood to an individual. An individual that is type A has A antigens on their red blood cells. Type B has B antigens on their red blood cells. Type AB has both A and B antigens. Type O has neither A or B antigens.

24. Copyright © 2013 Crosscutting Concepts, LLC. All Rights Reserved. www.CrosscuttingConcepts.com Biological Properties of Blood In addition to the A and B antigens there is also another antigen, the Rh factor. Its presence is indicated by a positive sign and its absence is indicated by a negative sign. This is appended after the A/B/O indicator.

25. Copyright © 2013 Crosscutting Concepts, LLC. All Rights Reserved. www.CrosscuttingConcepts.com Blood Type Frequency Type African American AsianCaucasianHispanic O+47%39%37%53% O-4%1%8%4% A+24%27%33%29% A-2%0.5%7%2% B+18%25%9% B-1%0.4%2%1% AB+4%7%3%2% AB-0.3%0.1%1%0.2%

26. Copyright © 2013 Crosscutting Concepts, LLC. All Rights Reserved. www.CrosscuttingConcepts.com Blood Origin Testing Two categories of tests are available for investigators. Presumptive tests are used to quickly determine whether an unknown substance is blood in the field. They are prone to false positives. Confirmatory tests must be done at a lab and provide much more accurate results.

27. Copyright © 2013 Crosscutting Concepts, LLC. All Rights Reserved. www.CrosscuttingConcepts.com Blood Origin Testing Two categories of presumptive tests are: –Color changing tests Luminol, Benzidine, Phenolphtalein, TMB / Hemastix –Glowing reaction tests fluorescein

28. Copyright © 2013 Crosscutting Concepts, LLC. All Rights Reserved. www.CrosscuttingConcepts.com Phenolphthalein Presumptive Test This test is better known as the Kastle-Meyer test. In a positive reaction the reduced phenolphthalein will turn bright pink because the phenolphthalein is oxidized by hydrogen peroxide in the presence of hemoglobin. Phenolphthalein reagents give false positives when vegetable materials are present.

29. Copyright © 2013 Crosscutting Concepts, LLC. All Rights Reserved. www.CrosscuttingConcepts.com TMB / Hemastix Presumptive Test This test is performed with commercial plastic strips with a treated filter at one end. A test swab is moistened with water and placed in contact with the stain. The swab is then placed onto the tip of the strip. If blood is present the hemastix strip will turn green.

30. Copyright © 2013 Crosscutting Concepts, LLC. All Rights Reserved. www.CrosscuttingConcepts.com Luminol Presumptive Test Luminol tests for latent bloodstains. It can detect blood that has been diluted up to 1 in 10,000,000. When luminol and hydrogen peroxide are applied to the bloodstain the luminol produces a blue- white to yellow-green light. Luminol can affect some testing processes but does not affect most blood typing or DNA analysis. It produces a false positive with plant enzymes, oxidizers, metals, and chlorine.

31. Copyright © 2013 Crosscutting Concepts, LLC. All Rights Reserved. www.CrosscuttingConcepts.com Fluorescein Presumptive Test Fluorescein tests for latent bloodstains by fluorescing under ultraviolet light. It can even detect blood stains that have been cleaned with solvents such as bleach. Fluorescein can also be applied to vertical surfaces, unlike luminol. Copper and hypochlorite will cause false positives.

32. Copyright © 2013 Crosscutting Concepts, LLC. All Rights Reserved. www.CrosscuttingConcepts.com Presumptive Test Summary Presumptive TestIndication of Positive Situation UsedFalse Positives PhenolphtaleinBright pink coloron visible stainsVegetable material (potatoes and horseradish) Tetramethylbenzidine (TMB) / Hemastix Green to blue- green color on visible stainsOxidizing agents, catalyst, vegetable peroxidase, cosmetics LuminolBlue-white to yellow-green light latent bloodPlant enzymes, oxidizing agents, metals, chlorine FluoresceinFluoresce with UV light source latent blood, vertical surface Copper, hypochlorite

33. Copyright © 2013 Crosscutting Concepts, LLC. All Rights Reserved. www.CrosscuttingConcepts.com Blood Origin Testing Once a stain has been characterized as blood through a presumptive test it is collected and stored for confirmatory testing. The two most common confirmatory tests are the Takayama and Trichmann tests.

34. Copyright © 2013 Crosscutting Concepts, LLC. All Rights Reserved. www.CrosscuttingConcepts.com Takayama Confirmatory Test The Takayama test is performed by adding an alkaline solution with a specific structure of hemoglobin to the stain on a microscope slide. If blood is present, pink crystals will be observed as the slide is heated.

35. Copyright © 2013 Crosscutting Concepts, LLC. All Rights Reserved. www.CrosscuttingConcepts.com Trichmann Confirmatory Test The Trichmann test is performed by adding a small amount of chloride containing acetic acid to the blood sample on a microscope slide. Small crystals form on the slide as it is heated if blood is present. Once the stain is confirmed as blood, it must be tested to determine if the source is human or animal.

36. Copyright © 2013 Crosscutting Concepts, LLC. All Rights Reserved. www.CrosscuttingConcepts.com Blood Origin Testing The precipitin test will determine whether the stain is of human or animal origin. The precipitin test uses an antigen that is designed to destroy human blood. This test takes advantage of the fact that antigens and antibodies naturally move toward each other on a gel plate. The extracted blood stain (antigen) and the human antiserum (antibody) are placed in separate holes opposite each other on the gel. If the blood is human, a line of precipitation forms where the antigens and antibodies meet.

37. Copyright © 2013 Crosscutting Concepts, LLC. All Rights Reserved. www.CrosscuttingConcepts.com Blood Properties Since the 1990’s DNA found in the blood and other bodily fluids has been used to identify an individual, like a genetic fingerprint.

38. Copyright © 2013 Crosscutting Concepts, LLC. All Rights Reserved. www.CrosscuttingConcepts.com Blood Properties DNA is unique to the individual, whereas blood typing can only eliminate an individual as a suspect. Blood type is class evidence and DNA is individual evidence. The process of genetic fingerprinting is called DNA profiling or DNA typing.

39. Copyright © 2013 Crosscutting Concepts, LLC. All Rights Reserved. www.CrosscuttingConcepts.com Detection Lab 1 Follow the lab procedures and record your data on the data collection sheet Make sure you observe the reactions within 3 minutes – if it is longer than that then the test is invalid

40. Copyright © 2013 Crosscutting Concepts, LLC. All Rights Reserved. www.CrosscuttingConcepts.com Exit Slip November 17, 2014 Go to m.socrative.com and enter 417101 Question: What did you observe when you tested the positive and negative control card?