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Trace evidence. Hair as evidence: day three. Getting started 2-4. Describe at least 3 characteristics that you can identify from the hair samples pictured to the right. Using hair as evidence. 5 types of hair from human body- dtrmd by x section 1. Head hair- usually circular
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Trace evidence Hair as evidence: day three
Getting started 2-4 Describe at least 3 characteristics that you can identify from the hair samples pictured to the right
Using hair as evidence • 5 types of hair from human body- dtrmdby x section 1. Head hair- usually circular 2. Eyebrows/lashes- circular/tapering ends 3. Beard/mustache- thick &triangular; usually coarse & may have double medulla 4. Body hair- oval or triangular depending on if area has been regularly shaved; hair from arms & legs usually has blunt ends or frayed from abrasion 4. Pubic hair- oval or triangular; buckling of hair usually present
Types of hair Beard hair Pubic hair Arm hair
Using hair as evidence- Treatment • Bleaching removes pigment granules, can make hair brittle and disturbs scales on cuticle • Dying- change in cortex
Collection of hair evidence • Questioned hair must be accompanied by an adequate number of control samples: 1. some from victim 2. possible suspects 3. anyone who may have deposited hair at the scene • Control samples- 50 full length hairs from all areas of scalp- pulled 25 full length pubic hairs
Today’s assignments • Today is your LAST DAY for hair assignments, so make sure you turn in all your work from this section.