Blood Lab Packet part II

Transcription

1 Name Period Blood Lab Packet part II Lab Partner Names I understand that I am working as a group but I am to answer all of the questions. I should not copy someone else s answers. Collaboratively working in a group to discuss the answers is allowed but copying someone s answers is not allowed. Therefore, my answers should not match any one else s work, word for word. I understand that if all of my answers are word for word as someone else s, I will receive a 0 for my lab packet. My understanding is demonstrated by my signature. I understand that this packet is due on the date that is due. If it is late, I will receive 50% off the first day it is late and no credit after the first day of being late. I need to make up any labs during class time or before school in case of an absence and all make up labs must be completed by the due date. My understanding is demonstrated by my signature.

2 Passive drops 1. Place a dropper of blood 45 cm above the paper. 2. Release one drop of blood onto the paper. Insert the picture of blood drop in the box below. Label the spines of the blood spatter Label the parent drop of the blood spatter Label the satellite spatters Passive drops: Height Vs. Diameter 1. Place the dropper of blood 15 cm above the paper. 2. Release one drop of blood onto the paper. 3. Circle the drop and write the height of the drop. 4. Repeat steps 1-3 at 30 cm, 45 cm, and 60 cm, 75 cm, 100 cm, 150 cm. 5. Fill out the data table below and graph your results. 6. Insert pictures of the blood spatter at different heights in the box below.

3 15 cm 75 cm 30cm 100 cm Height of dropper 15 cm 30 cm 45 cm 60 cm 75 cm 100 cm 150 cm Diameter of drop

4 Graph your results below X-axis is height of dropper and Y-axis id diameter of drop. 1. How does the diameter of the blood drop change as height changes? What is the relationship between height and diameter?

5 Blood spatter: Standing still or Movement 1. Stand still and place a dropper of blood about 30 cm above the paper. Drop the blood from this height without moving. 2. Lay out the paper across the floor. Run across the paper while dropping blood from the dropper. 3. Insert a picture of the blood spot from a stand still drop and a movement drop. Stand still Movement 1. How does the blood spatter differ if a person is standing still or moving? 2. How does the direction of the spines tell the direction of movement?

6 How does velocity of the blood affect the blood spatter? 1. Tape a piece of paper against the wall. 2. Hold your hand parallel against the paper. Your palms should be facing down. 3. Place some blood on the top of your hand. 4. Slap the top of your hand with the blood on it. The blood should spatter on the paper. This spatter represents blood moving at a medium velocity. 5. Place some blood on a toothbrush. 6. Hold the toothbrush vertical next to the paper. 7. Use your finger to swipe the bristles of the toothbrush. The blood should spatter on the paper. This spatter represents blood moving at a high velocity. 8. Fill out the data table below. Insert a photo for the for the blood spatter below: Medium velocity impact High velocity impact 1. How does the size of the individual blood drops change as the velocity of the blood increases? 2. What type of weapon can cause blood to move at medium velocity? 3. What type of weapon can cause blood to move at high velocity?

7 Other Blood Spatter Patterns: Weapon cast off: Place paper on the table. Place about one milliliter of blood along the edge of a plastic knife. Use a horizontal slashing motion in the direction of the surface. Go back and forth several times. Each time, note the pattern the stain makes as you sweep back and forth. Insert picture and description here. Arterial spurting: Tape paper on the wall. Using a syringe filled with blood, begin walking the length of the paper squeezing off short spurts of blood to simulate the beating of a heart. Note the shape and pattern of the stains as you move along. Insert picture and description here.

8 Transfer stains: Shoe: Place paper on the floor. Place blood on the bottom of a shoe. Press the bloodied shoe against the paper by walking across the paper. Note the shape and pattern of the stain relative to your direction of travel. Insert picture and description here. Transfer Stains: other: Place a piece of paper on the table. Select an object (hand, finger, scissors, ect.) and place blood on it. Press the bloodied object against the target surface and not the appearance of the stain. Insert picture and description here.

9 Wipes: Place paper on your table. Transfer blood to the paper to form a small puddle. Wipe up the blood in the same motion you would use to clean it. Note the appearance of the stain relative to the direction of travel. Insert picture and description here.

10 Angle of impact of passive drops 1. Hold a clip board flat on the table. 2. Place a notecard in the clip board. 3. Place a protractor on the table with the clipboard. The clip board should be at Hold a blood dropper 30 cm above the notecard. 5. Drop one drop of blood on the notecard. 6. Determine the angle of the blood drop (90 - the angle of the clipboard) 7. Write the angle of the blood drop on the notecard. 8. Repeat steps 1-7 every 10. Record your results in the table below. Insert pictures of the blood drop in the data table below. Angle of clipboard Impact angle Picture of blood drop Measured height Measure d width Calculated angle

11 Angle of clipboard Impact angle Picture of blood drop Measured height Measure d width Calculated angle

12 Angle of clipboard Impact angle Picture of blood drop Measured height Measure d width Calculated angle How does the height of the blood spatter change as the angle impact decreases? 2. How does the width of the blood spatter change as the angle impact decreases? 3. How does the appearance of the tail change as the angle impact decreases?

13 Area of conversion and origin of blood droplets 1. Place a piece of paper on the table. 2. Place a bloody sponge on the paper. 3. Measure the distance from the floor to the bloody sponge. 4. Place a piece of paper on the floor next to the sponge. 5. Hit the sponge with a hammer. 6. Blood spatter should be seen on paper on the floor. 7. Find the point of convergence using the blood spatter. Use a pencil to find the area of convergence. Circle this area. 8. Circle three of the blood drops that you used to find the area of convergence. 9. Calculate the impact angle for these blood drops. 10. Measure the distance from this blood drop to the area of convergence. 11. Use the impact angle of the blood drops and the distance to the area of convergence to calculate the origin of height. Data Tables Blood spot Height Width Angle of impact 1 Distance to Point of Conversation Calculated Height of origin 2 3

14 Actual distance of height of sponge from floor Calculated origin of impact (average) 1. How does your calculated origin of impact compare to actual origin of the sponge?

15 Insert photograph of blood spatter here with all work

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