Fingerprint+Chapter+AB

Multiple Choice 1. c. 10 weeks 2. a. plastic fingerprints 3. c. loops, whorls, arches 4. d. delta region

Short Answer 1. You make an imaginary line from the core to the delta and count the amount of ridges within that space. 2. An impression left on any surface that has patterns from the ridges of a finger 3. Fingerprints are formed during the 10th week of pregnancy. They are formed in the basal layer where new skin cells are produced. This layer grows faster than the epidermis and as it grows it collapses around the other layers of skin forming the unique indentions. 4. No the unique patterns cannot be ever be completely destroyed by any skin injury because the outer layer or skin protects the ridges underneath and because they will grow back. 5. a. Ninhydrin reacts with the amino acids in sweat, makes a purple or blue print b. Cyanoacrylate Vapor reacts also with amino acids, however it makes a white print c. Silver Nitrate reacts with chloride from salt in perspiration on the print combines with the nitrate to form silver chloride d. Iodine Fuming combines with carbohydrates in latent print