FRSC-1011 Chapter 8: Fingerprints - trent Questions and Answers (100% Correct Answers) Already Graded A+

Principles of fingerprints [ Ans: ] 1. individual characteristic 2. remains unchanged 3. systematically classified Individual characteristics [ Ans: ] determined by ridge characteristics -- minutiae - 150 minutiae per average finger unchanged [ Ans: ] middle layer of skin called dermal papillae is responsible for form and patterns of ridges - they do not change systematically classified [ Ans: ] 3 classes: 1. loops 2. arches 3. whorls loops [ Ans: ] - most common (60-65%) - ulnar loop: starts on pinky side - radial loop: starts on thumb side whorls [ Ans: ] minimum of 2 deltas What is the Henry system? [ Ans: ] An early system of classifying fingerprint patterns that requires all 10 prints to be filed What is the basis for primary classification in the Henry system? [ Ans: ] The presence of whorls Primary classification values [ Ans: ] whorls on 1st pair = 16 whorls on 2nd pair = 8 whorls on 3rd pair = 4 whorls on 4th pair = 2 whorls on 5th pair = 1 loops or arches on any fingers = 0 Exemplar prints [ Ans: ] prints intentionally collected Patent prints [ Ans: ] visible prints transferred onto a surface Plastic prints [ Ans: ] impressions found on soft surfaces that retain shape Latent prints [ Ans: ] not visible RUVIS [ Ans: ] Reflected Ultraviolet Imaging System, used for detecting latent prints without powder or chemicals 2 factors of developing and enhancing fingerprints [ Ans: ] 1. Type of secretion 2. Type of substrate print is deposited on Eccrine sweat glands [ Ans: ] palms, soles of feet - controlled by ANS - mostly water What do sebaceous glands produce? [ Ans: ] Sebum Where are sebaceous glands commonly found on the body? [ Ans: ] Hair covered places How can sebum get on your hands? [ Ans: ] By touching hair covered places Iodine fuming [ Ans: ] for porous surfaces, exposes prints to iodine vapors Ninhydrin [ Ans: ] chemical used on porous surfaces that reacts with the amino acids in the fingerprint to make a purple colour Cyanoacrylate (superglue) [ Ans: ] for non-porous surfaces What is the last resort reagent for fingerprint developing? [ Ans: ] Silver nitrate-based reagent When is silver nitrate-based reagent used? [ Ans: ] For a once wet porous surface What does silver nitrate-based reagent react with? [ Ans: ] Sebaceous secretions Molybdenum Disulfide or SPR [ Ans: ] wet non-porous surfaces 3 possible fing