28 terms

Hug Forensic Science Chapter 3 Hair

Bertino Forensic Science
class evidence
material that connects an individual or thing to a certain group. Hair without a root is class evidence.
comparison microscope
a compound microscope that allows the side by side comparison of samples, such as of hair or fibers
hair cuticle
the tough outer covering of a hair composed of overlapping scales
individual evidence
a kind of evidence that identifies a particular person, like DNA and fingerprints
hair follicle
The tube-like depression or pocket in the skin or scalp that contains the hair root.
the central core of a hair fiber
a type of fibrous protein that makes up the majority of the cortex of a hair
melanin granules
bits of pigment found on the cortex of a hair
flattened, overlapping scales commonly found in human and in many animal hairs.
trace evidence
small but measurable amounts of physical or biological material found at a crime scene
medulla pattern that has one unbroken line of color
medulla pattern where the line is unevenly spaced
you can use this common item as a model to remember the three hair parts
you can determine if some one is taking these from the chemical analysis of hair
body temperature
hairs main purpose was intended to maintain this
the hair from this race appears kinky, curled or coiled
the hair from this race has the largest diameter
you lose approximately one _____________________ hairs a day
sebaceous gland
secretes oil to help keep the hair conditioned
skin layer just below the skin surface
1.3 cm
average amount of hair growth per month. This can be used to establish patterns in hair coloring or in drug use.
Stages of hair growth
Anagen, Catagen, Telogen. Anagen is period of active growth; in catagen growth slows to a stop and hair is changing, telogen hair is dormant and may fall out.
medullary index
Determined by measuring the diameter of the medulla and dividing it by the diameter of the hair. Animal MI is 1/2 or greater. Human is 1/3 or smaller.
animal hairs
have a wider diversity of cuticle patterns than human, larger and more varied medullas, and different cross-sectional shapes
Gas Chromatography
a method of separating chemicals to establish their quantities that can be used to determine the presence of drugs and toxins in hair
straight or wavy, small and evenly distributed pigments, varies in color, red, brown, blond or black
Underlying, Inner Layer of the skin directly beneath the epidermis, is were the follicle is located
isotope analysis
Isotope analysis is the identification of isotopic signature, the distribution of certain stable isotopes and chemical elements within chemical compounds. Can be used to indicate travel, diet, etc.

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