FORENSICS: HAIR AND FIBERS QUESTIONS
a characteristic of natural fibers is that they...
are affected by microscopic organisms
what kind of evidence is the hair shaft?
class evidence
which of the following characteristics is found in typical Asian hair?
dark medulla
hair can be used to determine...
diet, drug habits, and geographic history
all hairs on the head of a person are identical
false
which part of a hair can be analyzed for nuclear DNA?
follicle
animal hair can be distinguished from human hair because animal hair...
has a greater medullary index and more variation in the cuticle patterns
human hair has which type of cuticle?
imbricate
microscopic hair analysis...
is used to exclude a suspect
what is true of fiber evidence?
it is analyzed using microscopes, it is possible to determine the composition and quantities of its chemical makeup using gas chromatography and a mass spectrometer, it is generally considered to be class evidence
the shiny nature of silk can be related to...
its ability to reflect light
what kind of protein is hair composed of?
keratin
which of the following is most likely a result of hair bleaching?
oxidized hair and damaged DNA
natural fibers can be harvested from...
plants, animals, AND MINERALS
mineral fibers such as asbestos are very durable. these fibers are used in what?
shingles, floor tiles, brake linings
what does the type of weave pattern affect?
shiny appearance, stretch of fabric, and strength of fabric
what two traits would indicate that the fiber was a human hair and not a piece of fiber obtained from an article of clothing?
the presence of a cuticle and a medullary index of 0.33 or less
what are the characteristics of synthetic fibers?
they are used in the production of carpet fibers, they are manufactured, they are formed by combining monomer compounds into polymer molecules
hair can provide clues about someones ancestry
true
which factors are used to calculate the medullary index of the hair?
width of medulla and width of hair
although variations can occur, which of the following best describes European hair?
straight or wavy with evenly distributed granules
the period when hair is naturally shed is called the -------- stage
telogen (tail end)
What characteristics of cotton make it a great source of fiber for clothing?
the fibers are easily woven and dyed
