Forensics U3 Fingerprints

What is a Radial Loop?

A loop that opens towards the thumb (less common)

What is an Ulnar Loop?

A loop that opens towards the pinky (more common)

What percent of people have loops?

60%

What percent of people have whorls?

35%

What's a plain whorl?

when a whorl only has one core

What's a Central Pocket Whorl?

a whorl with two deltas (one closer to the core)

What is a Double loop Whorl?

a whorl with two loops in one print but still two deltas

What is an accidental whorl?

a whorl that does not fall under any of the other whorl categories

what percent of people have arches?

5%

what is a Plain Arch

the simplest of all patterns

what is a Tented Arch

the more complex arch

Define a loop

the most common fingerprint. ridges entering and exiting from the same side. one delta.

Define a whorl

Second most common fingerprint. makes a complete circuit. two deltas

define arches

least common type of fingerprint. NO deltas. ridges enter on one side and exit on the other.

What does a Ridge ending look like?

What does a short ridge look like?

What does a dot/island look like?

What does a bifurcation look like?

what does a double bifurcation fingerprint look like?

what does a trifurcation fingerprint look like?

what does a bridge fingerprint look like?

what does an enclosure ridge on a fingerprint look like?

what does a spur/hook on a fingerprint look like?

A fingerprint is an _________ characteristic

individual

Fingerprint pattern will remain _______ for the life of an individual

the same

Fingerprints have general characteristics called _________ that allow them to be systematically identified

ridges/minutiae

what are the three types of fingerprints that you can find at a crime scene. define them

Patent - visible prints on a smooth surface

Plastic - indentations left in a soft material

Latent - not visible to the naked eye.

Powders - adhere to both ____ and ______, on a ______ surface

water, fatty deposits, nonporous

Iodine - fumes react with ____ and ______ to produce a _______ color, on a _________ surface

oils, fats, temporary yellow/brown, porous

Ninhydrin - reacts with ______ to produce a _______ color, on a ___________ surface

amino acids, circle, porous

silver nitrate - reacts with __________ to form _________, on a ____________ surface

chloride, silver chloride, porous

cyanoacrylate - "super glue" fumes react with ________ and other fingerprint constituents to produce a _________ color, on a _____________ surface.

water, white, nonporous

how can a palm print be found?

friction ridges can be identified

when are footprints taken?

at birth to identify infants

what are common lip patterns

Short vertical/horizontal lines, crosshatching, branching grooves

how is the retina used for identification?

blood vessel patterns in the eye may be unique to individuals.