Hair unit for Forensics

In what two ways can hair evidence be classified? What makes it classified one way vs the other?

individual evidence (with follicle has DNA) and class evidence (without follicle no DNA)

How can hair be useful to investigators if the follicle is not present/what information can hair give investigators?

If the follicle is attached DNA analysis can be performed (individual evidence) without the follice it is only class evidence but could tell the color length but nothing much more

List the 3 parts of the hair shaft.

cuticle (outer layer) cortex(middle layer) medulla (inner core of shaft)

Explain the function of the 3 parts of the hair shaft

coretex- middle of shaft makes up largest part embedded with color. medulla- center of hair shart it tells if a hair is human or not and gives characteristics. cuticle- outer layer

List 3 examples of the microscopic properties of hair.

pattern of medulla

color of the cortex

List 3 examples of the macroscopic properties of hair.

length, color,

length

color

If hair grows at a rate of approximately 0.44 mm per day

how many days has a hair been growing if it measures 40 mm from follicle to tip?

MI=

width of medulla/ width of cortex

if the medullary index is 0.33 or less the hair most likely is

human hair

medullary index 0.5 or greater

most likely animal har