Forensics (glass, paint, and hair analysis)

The entire hair is collected because a hair may show variation in color and other morphological features over its entire length.

True

 It is not necessary for questioned and standard/reference hairs to come from the same area of the body.

False

It is common to obtain a physical match for fibers.

False

The criminalist typically has many fibers available for analysis.

False

When tempered glass breaks, it does not shatter.

True

Density and refractive index are class characteristics, and a match does not meet the criteria for individualizing a glass fragment to a common source.

True

A fracture always terminates at an existing line of fracture.

True

Pyrolysis gas chromatography is NOT useful in paint analysis

False

It is not necessary that the collected paint from a vehicle involved in a hit and run accident be close to the area of the car suspected of having had contact with the victim.

False

Glass fragments removed from a single sheet of plate glass have a uniform density or refractive index value

False

When gathering soil specimens, standard/reference soils should be collected at various intervals within a 100 yard radius of the crime scene as well as at the site of the crime

True

Most glass fragments can be physically reassembled or fitted together by the criminalist

False

Hair is an appendage of the skin that grows out of an organ known as the hair _____.

Follicle

The _____ is embedded with pigment granules that give hair its color.

Cortex

The scale pattern of the cuticle is an important feature for characterizing _____ hair.

Species/animal

Forcibly removed hairs often bear follicular tags that are rich sources of _____ DNA.

Nuclear

Collecting _____ full-length hairs from all areas of the scalp normally ensures a representative sampling.

50

Fibers are classified as being either natural or _____.

Synthetic/manufactured

The _____of any given substance compares the speed of light in a vacuum to its speed through the substance

Refractive Index

_____ glass is used commonly in bottles and windows

Soda Lime

_____glass is glass made stronger by introducing stress through rapid heating and cooling of the glass surfaces.

Tempered

_____glass is created by sandwiching one layer of plastic between two pieces of ordinary window glass.

Laminated

Name and briefly define the 3 three layers of the hair shaft

-cuticle:  scales covering outer hair

-Medulla:  Column running through middle of hair

-cortex:  main body: contain color pigments

 What physical properties are used most often to characterize glass particles?  What is the main drawback of using these properties to characterize glass?

Density and refractive index

They are class characteristics and do not meet criteria for individualization