Fiber Analysis

Which two characteristics of a hair help determine if the hair came from a human or animal?

• Medulla pattern and cuticle type

• Color and length

• Thickness and texture

• Curliness and elasticity

Fibers are commonly examined by a microscope that changes typical scattered light wavelengths into wavelengths that vibrate in only one direction, which enhances contrast. This process describes which microscopy analysis?

• Polarizing Microscopy

• Comparison Microscopy

• Oblique Lighting Microscopy

• Transmission Electron Microscopy

Tags

NGSS.MS-PS4-2

A characteristic that differentiates synthetic fibers from natural fibers is that synthetic fibers —

• are very uniform in diameter

• contain webbing from spiders

• share a common polymer cellulose

• come from minerals that are mined from the ground

________________________ are derived from animals, plants, or minerals, while some ________________________ are petroleum-based products.

• Natural fibers, synthetic fibers

• Synthetic fibers, natural fibers

• Mineral fibers, animal fibers

• Petroleum fibers, plant fibers

Tags

NGSS.MS-PS1-3

At a crime scene, investigators collect blood, hair, and fibers that need to be packaged. What is the best method of packaging the evidence?

• Package hairs and fibers together and biological materials separately

• Package all evidence in paper bags with a proper seal

• Package all evidence separately in the appropriate container

• All evidence will be collected and packaged together

The following medulla pattern is called

• fragmented 

• continuous

• interrupted

Tags

NGSS.MS-LS3-1

Which of the following statements is not true about fiber evidence?

• To determine what it is you can burn it

• Looking under a microscope you can tell natural from synthetic

• Different weave patterns exist because different fabric has different purposes

• Fibers are considered individual evidence

What kind of hair is this?

• Human

• Animal

Tags

NGSS.MS-LS4-2

Which type of fiber is most likely to be affected by environmental conditions such as sunlight and moisture?

• A) Natural fibers

• B) Synthetic fibers

• C) Mineral fibers

• D) Metallic fibers

What is the primary method used to identify the chemical composition of a fiber?

• A) Chromatography

• B) Mass Spectrometry

• C) Infrared Spectroscopy

• D) Polarizing Microscopy