How can We Classify Fingerprints? TBT: Drug Identification Cold Call May 8, 2014 How can We Classify Fingerprints? TBT: Drug Identification Cold Call

Agenda Drug Analysis Lab Review Introduction to fingerprints Fingerprinting Fingerprint analysis Fingerprint characteristics

Drug Analysis What were the reactions you saw in the wells? What ingredient contained the aspirin? Follow your procedures!!!

What is a fingerprint? Unique patterns on our fingers Individual Circumstantial

What is a fingerprint? Markings left on objects we touch. Due to secretions (water, oil, salt) from sweat glands in our fingertips.

Fingerprinting By the end of this activity, you will be able to: Identify your fingerprints Compare your fingerprints to those of your classmates

Fingerprints You will each receive: Piece of clear tape Pencil Notecard

Fingerprinting procedure Rub your pencil back and forth on the lined side of your notecard, creating a small patch of graphite, about 2 x 3 inches. Roll your right index finger from side to side across the graphite patch. Your finger should be coated with graphite from fingernail edge to fingernail edge, and from joint to tip. Place the tape on your finger so that it goes from fingernail edge to edge. Gently peel off the tape. Press the tape into your notebook. Examine your print using a magnifying glass. Try to find any unique characteristics or patterns.

Fingerprint Characteristics

Loops Enter from right or left, and exit that same side

Arches Enter from one side, rise in the center, and leave from the other side.

Whorls Circular ridges, looks like a bull’s-eye

Fingerprint ID Take out your Fingerprint ID Sheet. What pattern did you have on your right index finger? We will now calculate the class’ average fingerprint pattern.

Class Average Calculation # of Loops / Total # of students # of Whorls / Total # of students # of Arches/ Total # of students

Population Percentages The following are percentages of the total population: Loops: 65% Whorls: 30% Arches: 5% How do our results compare?

Fingerprint ID How could this activity be improved? Accuracy Clarity of print

Fingerprint Principles A fingerprint is an individual characteristic; no two people have the exact same fingerprint A fingerprint pattern will remain unchanged for life Fingerprints have ridge patterns