Human vs Animal
Type of cuticle seen in humans rather than animals.
What is imbricate?
Microscopic hair comparisons must be regarded by police and courts as ___________ type of evidence.
Direct or indirect?
What is indirect?
Means a fiber was man-made?
What is synthetic?
What 2 tests can we use to analyze fibers?
microscopic analysis and burn test
Types of cuticles usually seen in animals rather than humans.
What is spinous and coronal?
The part of the hair that has DNA in it
Root
Natural fibers can come from:
plants or animals
What do synthetic fibers look like under the microscope?
smooth and straight
What are 3 kinds of analysis that can be done on hair?
DNA testing, drug testing, microscopic analysis
What is a synthetic fiber? Give 1 example
Man-made, (Examples: polyester, nylon)
What do natural fibers look like under a microscope?
Plants: twisted/ wavy
Animal: Lots of texture
How can looking at the cuticle help you tell the difference between animal and human hair?
The scale pattern:
Humans - imbricate
Animals - coronal (most likely animal) or spinous (always animal)
What kind of evidence is hair WITHOUT a root?
Known or Unknown
Direct or Indirect
Class or Individual
unknown, indirect, class
What is natural fiber? Give 1 example
Made from natural materials (comes from nature)
Examples: silk, wool, cotton
How do natural fibers react to the burn test?
Turn to ash
Light easily and burn quickly
How can the medulla help you determine if hair is animal or human?
The animal hair will have a thicker medulla than the human hair
Medullae may be classified as one of these 3
Continuous, broken, absent
What kind of evidence is hair with the root when found at a crime scene?
Known or Unknown
Direct or Indirect
Class or Individual
unknown, indirect, individual
What kind of evidence is fiber evidence?
Known or Unknown
Direct or Indirect
Class or Individual
unknown, indirect, class
How do synthetic fibers react to the burn test?
Shrink from flame
Chemical odor
Melt
Not as much smoke