Name: _____________________________Per.: _________ Date:_____________________________
Chapter 5 Hair Analysis
1. Morphology – form and structure
2. Polymer – a molecule consisting of many identical repeating units; polymers can be
naturally occurring or synthetic.
3. Cuticle – the tough, clear outer covering of the hair shaft composed of overlapping
scales.
4. Cortex – middle layer of the hair shaft that provides strength; comprises most of the hair
mass; the region of a hair located outside of the medulla containing granules of
pigments.
5. Medulla – the spongy, central, interior core of hair that gives it flexibility; appears as a
canal in the middle of the shaft
6. Keratin – A type of fibrous, tough protein polymer made up of about 20 amino acids that
makes up the majority of the cortex of a hair. The principle protein is cysteine, which
allows strong disulfide bonds to form between protein chains. All that sulfur in keratin
also accounts for the distinctive smell of burning hair.
7. Cortical fusi – irregularly shaped air spaces in the cortex
8. Undulation – in hair morphology, slight waviness
9. Anagen phase – period of growth in the hair cycle, averaging 3 – 5 years.
10. Catagen phase – intermediate period of hair growth, lasting about 3 weeks.
11. Telogen phase – final phase in hair growth, resulting in the loss of hair over about 3
months.
12. Interference patterns – patterns that demonstrate the wave nature of light, resulting from
constructive (additive) and destructive combinations of light waves. This happens when
a small object deflects coherent light so that the wave fronts travel different distances
which is called diffraction.
13. Melanin – a natural pigment found in the skin. UV rays in sunlight make it more
concentrated, causing tanning.
14. Melanin granules – bits of pigment found in the cortex of a hair.
15. Neutron activation analysis – a method of analysis that determines composition of
elements in a sample.
16. Association – a link between an unknown and known sample.
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Name: _____________________________Per.: _________ Date:_____________________________
17. Questioned – term used in forensics to describe a sample of unknown origin; for
example, a hair was found on a jacket, but we do not know whose head it came from.
18. Exemplar – term used in forensics to describe a sample of known origin; for example, we
know that this hair was pulled out of so-and-so’s scalp.
19. Metabolite – a specific product of a substance, formed by chemical processes in the
body.
20. False positive – a test result that comes out positive when it should not; often caused by
contamination or failure to run a control.
21. Hair follicle – the actively growing root or base of a hair containing DNA and living cells.
22. Trace evidence – small but measurable amounts of physical or biological material found
at a crime scene.
23. Class evidence – material that connects an individual or thing to a certain group.
24. Individual evidence – a kind of evidence that identifies a particular person or thing
Chapter 5 Hair Analysis Interesting Facts
1. Neither hair nor fingernails continue to grow after death, contrary to Johnny Carson’s
joke. The scalp shrinks and, with time, often slips off the skull in one piece, forming what
is known as a hair mask. The skin merely shrinks on the fingers so the nails appear
longer.
2. Most of us can grow only about three feet of hair before it stops getting any longer. The
world’s longest hair, according to Guinness World Records, with a length of more than
18 feet, belonged to Xie Quiping of China.
3. Microscopic examination of hair from the mummy of Ramses II showed that the pharaoh
was a natural redhead and that he used henna to accentuate his hair color. This is after
33 centuries!
4. The history of prescription drug-use by Henri Paul was determined by analysis of his
hair. He was the driver of the car in which he, Dodi Fayed, and Princess Diana died on
August 31, 1997.
5. All of the hair follicles in humans are formed when a fetus is five (5) months old.
6. You lose approximately 100 hairs from your head each day. These end up on your
clothes, in your hairbrush, on furniture and at the places you visit.
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