Hair And Fibre

Question 1

How is the length of a hair measured? What are the 3 layers?

Answer 1

Measured from root-tip

Cuticle - outer protective layer
Cortex - main body
Medulla - inner cell column

Question 2

What is analyzed about a hair?

Answer 2

Colour, structure, morphology (is it human? or animal?)

Maybe DNA analysis (case dependent)

Question 3

What are the 3 stages of hair growth?

Answer 3

Anagen phase: active growth
Catagen phase: stationary (no growth or fallout), root shrinks.
Telogen phase: hair falls out, root breaks down.

Question 4

When are special analysis requests made?

Answer 4

Out of place hairs (ie dog hair when wonder doesn’t own a dog).

Question 5

What is a stable isotope analysis?

What else is analyzed?

Answer 5

Stable isotope analysis: local H2O composition changes that of our hair.

Also scale structure, medullary index, medullary shape.

Question 6

How can fibres help with incidents?

Answer 6

Transfer between people (homicide, assault,)

Vehicle incidents (hit and run, fibers on vehicle from person being hit)

Break and enter (snagged on furniture, broken windows,)

Question 7

How are clothing fibres analyzed under the microscope?

Answer 7

1. Comparison of colour/diameter
2. If match, can look at striations or use delustering particles.

Question 8

What are some important details of the Anthony Case?

Answer 8

Hair on brush and trunk, girl buried in woods near house, Casey’s strange behaviour, car decomposition, not a lot of other evidence.