trace evidence
occurs as a result of physical contact between a suspect and victim/crime scene during a crime
examples of trace evidence
Fibers, hair, soil, wood, gunshot residue and pollen
compound microscope
used for viewing samples at high magnification (40 - 1000x), which is achieved by the combined effect of two sets of lenses: the ocular lens (in the eyepiece) and the objective lenses (close to the sample).
hair shaft
the part of a hair projecting beyond the surface of the skin (contains the cortex, cuticle, and medulla)
cuticle
the outermost layer; protects the inside of the hair shaft from damage.
cortex
The cortex of the hair shaft is located between the hair cuticle and medulla and is the thickest hair layer. It also contains most of the hair's pigment, giving the hair its color. The pigment in the cortex is melanin, which is also found in skin.
medulla
the innermost layer of the hair shaft; serves as the pith or marrow of the hair.
root
the part of the hair below the surface of the skin
follicle
A sac from which a hair grows and into which the sebaceous (oil) glands open. The follicle is lined by cells derived from the epidermal (outside) layer of the skin.
anagen
the growth phase
catagen
transitional phase
telogen
resting phase (hair falls out)
chemical testing methods
burn, acid, base, acetone
natural fibers
wool, silk, cotton, cashmere
synthetic fibers
polyester, spandex, acrylic, nylon