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• Blood and Body Fluids Notes and Labs 2003 Blood Function: Transport of dissolved gases (oxygen and carbon dioxide), nutrients, enzymes, etc. In addition, drugs, medicines, enzymes and neurotransmitters are transported. Drugs could include: nicotine, THC, LSD, cocaine, methamphetamine, alcohol. Toxicology tests for these. Neurotransmitt ers could include: dopamine, serotonin, GABA, Ach. Blood is composed of cells, RBC (erythrocytes – Hb carries oxygen and carbon dioxide), WBC (leucocytes from the immune system– kill foreign bacteria, cleaning the blood), platelets (used in blood clotting) and plasma Blood Types: A, B, AB, O and Rh factor DNA testing uses the DNA from the blood cell nuclei Hematocrit measure the % Blood cells Spin blood so that cells go to the bottom leaving yellow plasma at the top of the tube Plasma (55% of blood) is a straw colored part of the blood which is composed of water (90%) and 10% metabolites, waste, salts with ions, mostly Na +, Cl - HCO3- and proteins. Tests: Is it Blood? In order to test if a substance is actually blood, there are tests that can be performed using various chemical tests. 1. Luminol*: short uv, spray samples to see fluorescence 2. Kastle- Meyer reagent** + 3 % H2O2: wet filter paper, label with permanent ink or pencil touch stain to wet filter paper to transfer the substance to be tested add 2 drops of Kastle- Meyer reagent Add 2 drops of fresh 3 % hydrogen peroxide Observe color change will be pink in the presence of real blood 3. Ninhydrin solution: Procedur e: • Set up samples of white cloth and white paper towels with ketchup, Tabasco sauce, worceshire sauce, BBQ sauce,red food dye and real steak or beef blood from the butcher. *Luminol: 1.0 g luminal + .5 g Na2CO3 dissolved in 100 ml of distilled water, then add 0.70 g sodium perborate (or 0.965 g potassium iodate can be substituted). ** Kastle- Meyer reagent – This is a reduced phenolphthalein solution. KOH, phenolphthalaein and Zinc. After dissolved add ethanol to 500 ml store in a brown bottle in the refrigerator. Blood Typing: • ABO and Rh blood characterizations are important in forensic serology because it can be done quickly and relatively inexpensively. About 80% of the population are secretors which means that their blood type antigens are found in body fluids other than blood. The ABO Blood System: Blood cells can be covered with polysaccharides known as antigens which react with antibodies found in blood serum causing blood cells to coagulate in an agglutination reaction like a chemical precipitation reaction. There are 2 basic antigens A and B. A person’s RBC can have either or both or none i.e. A,B, AB, O. thte purpose of the antibodies in the serum is to attack invaders that enter the blood system e.g. viruses. Antibody coated viruses are destroyed by WBC i.e. vaccines. Thus, type A person produces anti-B antibodies or anti-B serum to destroy type B blood cells and vice versa. Type O has both anti-A and anti-B antibodies in its serum wrong blood type can be fatal in blood transfusions and organ transplants Generally 41% of a population are type A, 10% type B, 4 % type AB and 45% type O. • • Testing if agglutinatin occurs as follows: • Anti- • Anti• Blood type A B •+ ••A ••+ •B •+ •+ • AB •••0 • Rh factor is sometimes referred to as D antigen Rh+ people have it and Rh- do not. About 85% of the general population has Rh factor. Potential problems can occur between an Rh- mother and an RH positive baby. Late in pregnancy, some of the baby's blood may cross over into the mothr's blood. The mother will make anti Rh factor which is not a problem in the first pregnancy but could be in successive pregnancies. So, the mother is injected with anti-Rh antibodies to eliminate the Rh antigen before her own immune system responds and generates immunological memory against the Rh factor, endangering any of her future Rh+ babies. Lab: "Blood Typing" (used an ABO Rh kit from Flinn Scientific) Lab: Blood Spatter Analysis: Using simulated blood (diluted Karo Syrup with Red and Blue food dye), students took platic knifes and spattered simulated blood onto white butcher paper at different angles outside the class room. BODY FLUIDS: • Body fluids can be saliva, mucous, semen, vaginal fluid, breast milk, or urine. These body fluids can carry metabolites (waste products), drugs, medicines, AB and Rh antigens, proteins, hormones, salts (electrolytes)and sugars. There exists a secretory gene (Se) in about 80 % of the population independent of your blood type i.e. a person could be type A and Se or type B and Se etc. This gene interacts with blood type genes and determines your ability to secrete your blood type antigens into body fluids and secretions. In other words secretors put blood type antigens into the blood and nonsecretors put little to no blood type antigens into the blood. Persons who are secretors can have their body fluids tested for blood type. These people also tend to have strong immune systems, therefore it is better to be a secretor than a non-secretor. • URINE: is composed of 95% water and 5% is other dissolved or suspended substances including carry metabolites (waste products), drugs, medicines, AB and Rh antigens, proteins, hormones, salts (electrolytes)and sugars. In generaly 0.6 to 2.5 liters of urine are produced by one person, depending on intake and environment i.e. temperature and humidity. If a person is diabetic, their urine may contain glucose. • LAB tests for urine: (setup for 3 different samples) 1. Tests include, density (specific gravity), pH, sugar and protein. 2. Teacher Notes: 3. Students need approximately 60 minutes to perform the tests: 4. Purchase synthetic urine or make urine from the following recipes 1. A: normal urine:160 ml of water + drops of yellow food coloring + 2.0 grams NaCl 2. B. add 40 ml of apple juice to 66 ml of normal urine A 3. C. Add a few drops of egg white (albumin) • A crime scenario can be put in place here (student or teacher generated) • LAB for urine (this lab based on Lab 3-1 "Don't flush the evidence", p. 127 of Crime Scene Investigations, Walker and Wood) 1. Materials: 1. centrifuge 2. pyrex test tubes to hold 20 ml 3. hot plates 4. 250 ml beakers (for hot water baths ) 5. 100 ml beakers (for urine samples) 6. Benedict's Solution 7. pH paper 8. Samples of synthetic urine 2. Procedures: 1. Obtain crime scene urine and urine 2. 3. 4. from the 2 suspects Make a Data Table for the three samples and 4 tests and observation s: specific gravity, pH, albumen (+ or -), glucose (+ or -), color odor and clarity Record odor, color (yellow, amber, gold, etc.) and clarity (clear, cloudy, etc.) Determine specific gravity (density) using a balance and graduated cylinder. Record results. 5. 6. Test for pH using pH paper and record results. Test for albumin: centrifuge 10-15 ml of each urine sample (label each test tube with water proof pen), remove supernatant into 2 clean test tubes. Place one in a hot water bath for 2-4 minutes, compare clarity with original sample, if it becomes more cloudy then albumin is present and record a + in data table. 7. Repeat for other samples. Test for glucose: Add 10.0 ml of each sample to a pyrex labelled test tube, add 10 drops of Bendict's solution to each of the 3 samples and to a test tub of water. Place all four test tubes into a hot (not boiling) water bath. Observe and record color. If the blue changes to yellow or gold, then glucose is present and put a + in your data table. • References: "Biology" fifth edition Neil A. Campbell, jane B. Reece, and Lawrence g. Mitchell, Addison wesley Longman. ISBN 0-8053-65664 intesting site on urine: http://www.heartlandh ealing.com/pages/archi ve/urine_therapy/ "Cr ime Scene Investigations - Real Life Science Labs for Grades 6-12" by Pam Walker and Elaine Wood ISBN 0-87628135-8 Prentice-hall (Simon and Schuster) by The Center for Applied Research in education.