Term
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Definition
- Made of keratin
- Dead
- Made in follicles |
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Term
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Definition
- Cylindrical tube
- Papilla found at base which is supplied with blood
- Develop in the womb around 8 weeks |
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Term
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Definition
| Trichonodesis - Knots in hair |
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Term
| Refractive index of hair + Problems |
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Definition
- RI = 1.55
- use of mountant means to toxicology or DNA |
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Term
|
Definition
- 100,000 to 200,000 on scalp
- 1 strand can hold upto 100g
- lose around 75-100 per day
- same number of follicles as other mammals just smaller |
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Term
|
Definition
- Protection
- Insulation
- eyebrows - stop sweat
- eyelashes - stop particles |
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Term
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Definition
- Woolen fabrics - linear over time
- Non-woolen - fabrics - exponential |
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Term
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Definition
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Term
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Definition
- straight
- Curved
- Loose
- Wavy
- Degree of curl can be measured |
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Term
|
Definition
- Cut
- Rounded
- Abraded
- Burnt
- Frayed
- Crushed |
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Term
|
Definition
- Cuticle
- Cortex
- Medulla |
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Term
|
Definition
- Made of overlapping scales
- chemically resistant
- Protects inner layers |
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Term
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Definition
- Made of cells and intercellular binding
- pigment granules determine colour in the hair
- makes up 90% of the hair
- Controls elasticity |
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Term
|
Definition
- made up column of proteins
- absence of medulla, determines fineness
- Drugs and hygiene effect this layer |
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Term
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Definition
- Anagen
- Catagen
- Telogen |
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Term
|
Definition
- Growth phase
- around 80-90%
- Attached at papilla
- 2-6 years |
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Term
|
Definition
- Intermediate stage
- detached from papilla
- last a few weeks
- Enzymes breakdown follicular cells |
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Term
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Definition
- Resting phase 10-18%
- New hair begins to grow
- no further growth of initial hair |
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Term
|
Definition
- Course
- distinctive kinks
- abraded tips
- slow growth
- large diameter |
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Term
|
Definition
- soft
- uniform in diameter
- vary in length
- narrow medulla
- tips and cut or split
- Exposed to environment |
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Term
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Definition
diameter of the medulla / Diameter of teh shaft
<1/3 = human
>1/2 = animal |
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Term
|
Definition
- Enter hair in 3 days and lasts months
- During anagen phase
- Diffusion from blood
- Diffusion from secretions
- External contamination |
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Term
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Definition
- 10-15mg
- Clean hair in ethanol at 37 degree for 15 mins
- 3 x 30min ph7 wash
- removes oils and cosmetics |
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Term
|
Definition
apply hair to 0.1N Hcl solution overnight
- hair still in tact
- analyse solution with hplc or gc-ms |
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Term
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Definition
- no training required
- stable sample
- non-invasive
- can detect 'one-off' use
- cant be tampered |
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Term
|
Definition
- expensive
- does not always detect small amounts
- false positives from external source
- hair can take 3 weeks to reach surface |
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