Bellringer 1. What is “serology”? 2. What body fluids do you think would fall under this study? Serology Objectives: 2.0 Explain ways to collect and preserve evidence from a crime scene. 2.1 Distinguishing between physical evidence and witness evidence 2.5 Describing ways to identify hair, fiber, and blood evidence 4.0 Describe presumptive and confirmatory tests. Examples: blood type comparison, DNA testing. 5.0 Describe the importance of genetic information to forensics. Bodily Fluids • Blood • Saliva • Tears • Perspiration • Pus • Semen • Human milk • Which 2 bodily fluids do you think are most common at crime scenes? DANGER!!! • What would be potential dangers of working with bodily fluids? • What precautions should be taken? Secretors vs. nonsecretors • From what fluids can blood type be determined? • 65-80% of the population can be blood typed from their body fluids. • These people are known as secretors. • What body fluid (other than blood) is easiest to blood type? Components of Blood 1. RBC’s – 1. Red blood cells 2. Transport oxygen and carbon dioxide 2. WBC’s – 1. White blood cells 2. fight infection 3. Platelets – help in clotting 4. Plasma – contains salts and proteins Blood Types? • Based on proteins: – Antigens – on surface of RBC’s – Antibodies – in plasma • A • B • AB • O • Additional subgroups (proteins on RBC’s) • Which type is most common? • Which is least common? Blood Types 1. Type A has: 1. A antigens on RBC surfaces and 2. B antibodies in plasma 2. Type B has: 1. ? 2. ? 3. Type AB has: 1. A and B antigens 2. NO antibodies 4. Type O has: ??? Rh Factor Blood Grouping • Rh factor is another antigen found ____________. • Rh+ means you have the antigen. • Rh – means ??? • Rh – DOES NOT mean you have Rh antibodies in the ________, but you may develop antibodies if you receive Rh+ blood. • Rh + people can receive Rh- blood with no problems. Blood Groupings • On a separate sheet of paper: 1. List all the possible blood groups. 2. Tell which blood types can receive blood from each blood type. Favorite College Teams • Alabama (U) • Auburn (A) • If you like U, you DON’T like ____. • If you like A, you DON’T like ____. Favorite College Teams, continued….. • If you like A, you are ANTI- ____. • If you like U, you are ANTI- ____. • Some fans will actually FIGHT fans of the other team. (antibodies) Favorite College Teams, continued….. • A new twist: • You can be for U or A, and indifferent to Florida (F) - although I can’t understand that kind of mentally. • HOWEVER, how do you feel about F if they are playing your team in the SEC championship game? Favorite College Teams “Blood Types” Assignment • Identify the following and give 1-letter symbols: 1. Favorite team 2. “Enemy” team 3. A “neutral” team 4. A 2nd-favorite team Favorite College Teams “Blood Types” Assignment • Write the symbols for each combination of “blood type” you can make from these teams, and what each symbol means.
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