major features of hair evidence
Compare and contrast the major features of hair evidence and
describe one collection technique to recover a hair specimen.
What is a hair
follicle? Name the major parts of the follicle.
A hair follicle is a part of the skin, which grows a hair
by packing old cells together. Attached inside the top of the follicle are
sebaceous glands, which are tiny sebum-producing glands in almost all skin
except on the palms, lips and soles of the feet. The thicker the hair, the more
the number of sebaceous glands there are. Also attached to the follicle is a
tiny bundle of muscle fiber, called
the arrector pili, which is responsible for causing the follicle lissis to
become more perpendicular (upright) to the surface of the skin. The muscle area
can also cause the follicle to stick up slightly above the nearby skin
(piloerection) with a pore incased with skin oil. This process results in goose
bumps (or goose flesh). Stem cells are at the junction of the arrector and the
follicle, and are principally responsible for the ongoing hair production
during a process known as the Anagen stage.
Select a line of
human descent and discuss the major characteristics of a sample of hair
from this descent line.
least one type of collection technique used to recover hair from a crime
possible, use the fingers or tweezers to pick up hair, place in paper bindles
or coin envelopes which should then be folded and sealed in larger envelopes.
Label the outer sealed envelope. If hair is attached, such as in dry blood, or
caught in metal or a crack of glass, do not attempt to remove it but rather
leave hair intact on the object. If the object is small, mark it, wrap it, and
seal it in an envelope. If the object is large, wrap the area containing the
hair in paper to prevent loss of hairs during shipment. In rape cases, the
victim’s pubic region should be combed prior to collecting standards. Obtain
known hair samples from the victim, suspect, or any other possible sources for
comparison with unknown specimens. The recommended method for collecting head
hairs is to start by having the person from whom they are being collected bend
over a large sheet of clean paper, rubbing or massaging their hands through the
hair so that loose hair will fall out on the paper. More should then be
gathered by plucking them from representative areas all over the head. A total
or 50-100 hairs is desired. Do not cut the hair. This same method may be used
to collect hairs from other parts of the body. 30-60 pubic hairs are required.
When the person is a suspect, hair should be gathered from all parts of the
body even though there may only be an interest in hair from the head at that
particular time. I NEED HELP ON THE SECOND QUESTION