Fingerprinting

FINGERPRINTING The skin on the palms of your hands and the soles of your feet is covered with tiny raised lines, called friction ridges. these ridges allow people to pick up and handle objects easily. Each person, even an identical twin, has a totally unique pattern of ridges on his or her hands and feet. The pattern on each finger or toe is unique and different from the pattern on every other finger or toe. A fingerprint is an impression of these ridge patterns transferred to another surface. Fingerprints occur because glands in our hands and feet secrete liquids, mainly sweat and oils. These liquids leave the patterned mark of our fingerprints on almost everything we touch. TAKING FINGERPRINTS Materials magnifying lens  ink pad  white paper  helper Procedure 1. Look at your fingerprints through the magnifying lens and examine the patterns on your skin. These are your fingerprints. 2. Make a set of your fingerprints.  a. Press one finger at a time into the ink pad, being careful not to get your fingers too wet.  b. Have your helper make your fingerprints by holding your hand steady and pressing and rolling your fingers one at a time onto a clean sheet of white paper. Be careful not to smudge the prints. CLASSIFYING FINGERPRINTS There are several ways to classify fingerprints. You are going to use one of the most basic ways. More complex classification systems break down the common fingerprint patterns into smaller groups.