Hair Evidence
Hair can adhere to clothes, carpets and other surfaces and be transferred to other locations. This is called:
What is secondary transfer?
Hair consists of two parts
What is a follicle and a shaft?
True or False: All hairs on the human head are identical.
What is false?
These are woven into textiles and fabrics.
What are fibers?
Fibers that have been spun together are called:
What is Yarn?
All mammals have hair. Its main purpose is to:
What is regulate body temperature through insulation?
The shaft is made up of three layers
What is the cuticle, cortex, and medulla?
True or False: Hair can provide clues to a persons ancestry.
What is true?
Forensic scientists use these to gather fiber evidence.
What are tweezers, tape and vacuums?
These all provide natural fibers.
What are animals, plants, and mined minerals?
True or False: Hair easily decomposes.
What is false?
This is the largest part of the hair shaft.
What is the cortex?
Since hair grows out of the skin, chemicals that the skin absorbs can become incorporated into hair. When ingested or absorbed these can be detected by chemical analyses of hair.
What are dugs, and toxins/ poisons?
This is when fibers are transferred directly from victim to suspect or suspect to victim.
What is direct transfer?
All plant fibers share this common polymer.
What is cellulose?
Hair is commonly considered this type of evidence.
What is class evidence?
Humans generally have these types of medulla patterns.
What are none or fragmented?
Hair viewed for forensic investigations is studied both macroscopically and microscopically.
Microscopic characteristics include:
What is the pattern of the medulla, pigmentation of the cortex, and types of scales on the cuticle
When using fiber as evidence, forensic scientists will ask questions about these things.
What is type of fibers, number of fibers, fiber color, location of fibers, fiber origin, and time between crime and fiber?
Animal provides fibers from these 3 sources.
What is fur, hair and silk?
This must be present for hair to be considered as individual evidence.
What is hair follicle/follicular tag?
This type of protein is made of a chain of amino acids that makes our hair both strong and flexible
What is Keratin?
Animal hair and human hair have several different characteristics, they are these 3 things:
What is the pattern of pigmentation, the medullary index and the cuticle type?
Fibers are classified into two groups.
What is Natural fibers and synthetic fibers?
Man-made fibers are broken into these two groups.
What is regenerated fibers and synthetic polymer fibers?