Page 207 - Demo

“Your Safer Source for Science”
Forensics
205
Forensics Blood Evidence, continued
Kastle-Meyer Presumptive Blood
Testing—Student Laboratory Kit
By: The Flinn Staff
Students feel like authentic crime scene investigators when they test for the presence of real blood! Four evidence samples, that may contain blood, are taken from a crime scene. Students perform the Kastle-Meyer test on each sample as a presumptive test to determine if further examination is needed. Learn about the benefits and limitations of presumptive blood testing to ignite further curiosity about forensic testing.
Complete for 30 students working in pairs. Approximately 20 mL of real blood are required, but not included. This can be obtained from a local butcher.
Kastle-Meyer Reagent—Forensic Test
Classic test for the presence of blood at a crime scene! Kastle-Meyer reagent contains reduced phenolphthalein indicator in a basic solution. Simply wipe a presumptive bloodstain with a cotton swab, add a drop of the reagent, and then apply a drop of hydrogen peroxide. If the swab turns pink rapidly, it is positive for blood! For a terrific guided-inquiry forensic activity, use the Kastle-Meyer reagent to investigate substances that will interfere with the test to give false positives.
Forensics DNA Evidence
Flinn Forensic Files—DNA Verification
See page 201.
Electrophoresis and DNA Forensics—General, Organic and Biological Chemistry Experiment See page 13.
Who’s the Daddy? DNA Profiling—
Super Value Kit
By: The Flinn Staff
Discover the power of DNA profiling (fingerprinting) using this creative simulation. No expensive equipment or chemicals needed! This activity only requires paper and scissors. Students solve a paternity case as they re-create each step of the DNA fingerprinting process. After assembling double-stranded DNA “molecules,” students cut them into fragments to simulate restriction enzyme digestion and then separate the fragments by size in a simulated gel. Next the DNA fragments are “denatured” (cut into single strands), “blotted” (pattern copied onto a sheet of paper), and treated with simulated radioactive probes that combine with only specific base sequences. The resulting simulated autoradiograph iden- tifies target DNA fragments, which are used to match the unidentified parent. This is a great teaching tool for students to learn how DNA fingerprinting really works! Includes black-line masters of simulated DNA segments, “radioactive probe” locators, electrophoresis gel blot- ter, magnetic tape, and zipper-lock bags.
Super Value Kit is complete for 30 students working in groups of six. All materials are reusable.
Kastle-Meyer Presumptive Blood Testing—Student Laboratory Kit AP7762
Catalog No.
Description
Price/Each
AP7762
Kastle-Meyer Presumptive Blood Testing— Student Laboratory Kit
$31.75
Catalog No.
Description
Price/Each
AP7555
Kastle-Meyer Reagent, 100 mL
$11.15
Kastle-Meyer Reagent—Forensic Test AP7555
Catalog No.
Description
Price/Each
FB1758
Who’s the Daddy? DNA Profiling—Super Value Kit
$20.40
FORENSICS DNA EVIDENCE continued on next page.
Who’s the Daddy? DNA Profiling—Super Value Kit FB1758