From Review Guide Flashcards
List three body parts that have ridges and furrows
Fingertips, palms, toes and feet
Why do fingerprints offer an evolutionary advantage? Two reasons
- The fingerprint stays the same your whole life
- Everyone has unique fingerprints so it makes it easier to narrow it down to one person
Explain the Bertillon identification system? Why was it not useful?
Body measurement system that measured body parts and identified people by their body measurements.
Will and William west case where other people could also have close to the same measurements
Which two scientists are credited with the fingerprint classification system used in the US and Europe today?
- Francis Galton
- Sir Edward Henry
What is raised structures on the tips of fingers?
Ridges
What creates the ridges on the surface?
Papillae
What is the outermost layer of skin?
Epidermis
What is the layer of skin that contains papillae?
Dermis
What is the layer of the skin that contains sweat glands and nerve cells?
Dermis
What is the white space left in the fingerprint patterns?
Furrows
What is the black space left in Fingerprint patterns?
Ridges
List FOUR components left by your fingers when you touch something?
- Sweat
- Oil
- Amino acids
- Salts
Why don’t twins have identical fingerprints?
The basal layer grows faster than the dermis and epidermis which collapses and creates different patterns.
DIFFERENT ENVIRONMENT
How many deltas and cores does whorl, loop, arch have?
Whorl: 2 deltas, 1 core
Loop: 1 delta, 1 core
Arches: 0 deltas, 0 cores
Compare radial and ulnar loops?
Radial is towards the pinky
Ulnar is towards the thumb
Compare plain and tented arch?
Plain is like a sand dune very small dunes
Tented arch looks like a pointed hat or like a blanket over the high dune
Compare plain and central pocket loop whorl
Plain whorl is like a swirl a big one
Central pocket loop whorl is the swirl in the middle that is in the center and other stuff are around it
What is dusting?
Using powder and brush to visualize the print
On smooth surfaces
What is iodine fuming?
What surface?
Iodine reacts with fatty oils in the skin
Non metallic
What is Ninhydrin?
Surfaces?
Reacts with amino acids. Sprayed on paper it turns purple.
Cloth, paper
What is silver nitrate?
Surface?
Reacts with salt
Salt and sweat
What is superglue fuming?
Surface?
Melts and fumes attach. Leaves white impression
Non porous. Metal, glass, plastic
What is the chemical found in superglue that adheres to fingerprint?
Cyanoacrylate
Plastic type
Print left in soft materials
Clay, wax, soap, play dough
Patent (visible) type
Left by liquids
Blood, ink
Latent type
Prints that are invisible to the naked eye. Can only be seen with proper equipment.
