Hair ID
Hair Layers
Fiber Stuff
Hair Evidence
FACTS
100
What is the central canal running through many hairs known as?
Medulla
100
What are the 3 layers of the hair shaft?
Cortex, Medulla, Cuticle.jpg)
100
Name a Natural Fiber
Cotton, Wool, Silk, Linen, Hemp etc.
100
Which hair feature is most important when determining species?
Scale Pattern
100
The medullary index of human hair is ______ the medullary index for most other animals.
Less than
200
Medullae can be classified as: _______, ________, ________, _________
Absent, Fragmented, Interrupted, Continuous
200
What layer of the hair is most resistant to chemical decomposition?
Cuticle
200
Name a Synthetic Fiber
Nylon, Plastic, Polyester, Rayon, Acrylic
200
What stage of the hair cycle is hair most easily lost?
Telogen
200
A person from what race would most likely have continuous medullae?
Mongoloid
300
Hair sample with "string of pearls" for medulla is from what animal?
Deer
300
Pigment granules can be found in this layer of hair.
Cortex
300
Before the 20th Century, all fibers were considered........
Natural
300
Human hair in cross-section appears flat in shape, would most likely be considered what race?
Negroid
300
What is the average length of hair growth over 1 month?
1 cm
400
Determining whether a hair belongs to a male or female would depend on......
DNA analysis
400
What are the 3 stages of hair growth?
Anagenic, Catagenic, Telogenic
400
What can be used to compare fibers? ______, _______, ________
Color, Diameter, Cross-section
400
Nuclear DNA typing can be most successfully accomplished on hairs removed during which stage of the hair cycle?
Telogenic
400
Human head hair is best characterized by what?
scale pattern
500
The cortex contains _______ which give the hair its color.
Pigments
500
Layer of the hair that contains "scales" which point towards the tip.
Cuticle
500
Certainty of common origin between two fibers can be determined when.......
they can be fitted together at their torn edges
500
This type of hair collection is most likely to provide useful DNA evidence.
Forcibly removing the hair, contain follicle
500
Which plant fiber is the most prevalent?
Cotton