types of finger prints (forensics q3)

When do fingerprints begin to develop during gestation?

Fingerprints begin to develop in the 10th week of gestation.

When does fingerprint development complete?

Fingerprint development completes during the 24th week of gestation.

What factors affect fingerprint development?

Chance, environment, and heredity effect fingerprint development.

What are the three principles of fingerprints?

1. Individual characteristics 2. No two fingers have the same print 3. Remain unchanged during a lifetime.

What are the three types of fingerprints?

1. Plastic impressions 2. Visible prints 3. Latent prints.

What is the definition of plastic impressions of fingerprints?

Prints made in soft material like butter, soap, etc.

What is a visible print?

Prints made when fingers have been covered in blood, dirt, oil, paint, etc.

What are latent prints?

Latent prints are not visible to the human eye until treated.

What percentage of the world has loop fingerprints?

60% of the world has loop fingerprints.

Describe the structure of loops in fingerprints.

Ridges start on one side, rise towards the center, and return back to the side they started.

How many deltas do loops have?

Loops have 1 delta.

What are the two types of loop fingerprints?

Radial (thumb) and ulnar (pinkie).

What percentage of the world has arch fingerprints?

5% of the world has arch fingerprints.

Describe the structure of arches in fingerprints.

Arches start on one side, rise towards the center, then leave on the other side.

How many deltas do arches have?

Arches have no deltas.

What are the two types of arches?

Plain arch and tented arch.

What percentage of the world has whorl fingerprints?

35% of the world has whorl fingerprints.

Describe the structure of whorls in fingerprints.

Some ridges form circles or spirals.

How many deltas do whorls have?

Whorls have 2 deltas.

What are the four types of whorls?

Plain, central pocket whorl, double loop, and accidental whorl.

What is a delta in fingerprint analysis?

A place where lines run side by side and then diverge with a significant recurving line, shaped like a triangle.

What is the core in fingerprint analysis?

The inner part of the last ridge in a fingerprint.

How many minutiae points must be found to match a print from a scene to a person?

At least 12 points must be found to match a print.

How should minutiae points be recorded on a fingerprint?

Label each with a number and a line to show location, and make a key at the bottom of the print.