Fingerprints and ACE-V Methodology Quiz 4

Study of friction ridge formation, in sequence, with sufficient detail to individualize.

Classified as an organ. Largest organ in the body. Two main layers: Epidermis (outer layer). Dermis (inner layer).

Made up of several smaller layers. Innermost layer most important because it is “genereting layer”.

Layer of skin in animals that leather comes from. Contains blood vessels, glands, and nerves. Provides generating layer with nutrients.

Cuts through epidermis that reach dermal papillae will leave scar as healthy skin cells cannot be regenerated due to damage to generating cell layer.

Double rows of peg-like areas in dermis that provides nutrients to “generating” layer.

12 weeks friction ridges start to form. Tension and pressure created by volar pads shape and alter patterns.

At 6 weeks some pad start to appear. At 10 weeks pads are prominent and thumb is rotated.

Arches usually have low pads. Whorls believed to form from high-centered pads. Loops form from intermediate pads.

Contain no sweat pores. Look like misprints or smaller, underdeveloped ridges. Can use for identification.

Loops 65%. Whorls 30%. Arches 5%.

ANY recurve at all is a loop. 1 core, 1 delta.

Run one side to the other, with no backward turn. 2 types: Plain and Tented. 0 cores, 0 deltas.

Even ridge flow from side to side. No significant “up thrust”.

Have significant up-thrust and don’t have same “easy” flow pattern as plain arches.

Some ridges make a turn through at least one circuit. Any pattern with 2 or more deltas.

Plain Whorl. Central Pocket Loop Whorl. Double Loop Whorl. Accidental Whorl.

One or more ridges which make or tend to make a complete circuit. 1 core, 2 deltas.

At least one recurving ridge or obstruction at right angles to line of flow. Ridges make one complete circuit which may be spiral, oval, circular, or any related variant. 1 core, 2 deltas.

2 separate and distinct loop formations with 2 separate and distinct shoulders for each. One or more ridges make complete circuit. 2 cores, 2 deltas.

Consists of two types of patterns with the exception of the plain arch. 1+ cores, 2+ deltas.

Sufficient unique details present that when compared a conclusion can be reached.

Substrate. Matrix. Development medium. Deposition pressure. Anatomical orientation.

Analysis for no value conducted prior to and regardless of whether comparisons will be conducted. Can still be used for exclusions.