Forensics – Unit 2 Study Guide
Fingerprints
List the three types of fingerprints that could be found at a crime scene.
1.
2.
3.
For methods of lifting fingerprints refer to diagram that you drew.
Are fingerprints considered class or individual evidence? Why or why not?
Ridge characteristics can be found on what three areas of the body?
1.
2.
3.
What are the three main types of fingerprint patterns?
1.
2.
3.
Which pattern is the most common one found in the population? ______
Which pattern is the least common one found in the population? ______
True or False Do fingerprints change over time on an individual?
The Primary Henry Classification identifies the presence of ______patterns on fingers and each finger is assigned a number based on the presence or absence of that pattern on that particular finger.
The Secondary Henry Classification is used to calculate the ______of a particular fingerprint pattern on a finger in the population.
What type of classification is used to match an unknown print to a known print?
What are minutiae? How are they used in fingerprint ID?
Hair
Why is hair important evidence (hint: think about its structure).
Is hair considered class or individual evidence? Why or why not?
How can hair and fibers have probative value?
Hair morphology (label the different parts of a hair):
Medulla
Cortex
Cuticle
What area is the pigment located? ______
What protein is hair mainly composed of? ______
What are some structural ways in which human hair differs from the hair of other mammals?
Cross sectional shapes of hair: Round, Oval, and Crescent (risky to assign to racial characteristics to hair).
True or False Can medulla patterns (i.e. continuous, interrupted, fragmented, none, etc.) vary among individuals and among hairs of an individual?
Three growth phases of hair are anagen, catagen, and telegen. At which phase would hair be most likely to have a follicular tag (composed of skin and blood cells) if it was pulled out? Why would a follicular tag be important for a crime investigation?
What would a forensic scientist do after collecting hair from a crime scene? (What characteristics would be used from the hair).
How can hair be a chemical indicator or how can one get a false positive from a hair sample?
Fibers
What are the two main types of fibers – give examples of each.
1.
2.
Is hair considered class or individual evidence? Why or why not?
Synthetic fibers are made of ______(long chains of repeating chemical units called monomers).
What does fabric consist of?
What is the warp and weft on a piece of fabric?
How is synthetic fiber made?
What are some ways that you would go about identifying fibers?