Hair
Human hair has which type of cuticle?
imbricate
Hair consists of 2 parts what are they?
follicle and a shaft
In humans, the cuticle is the largest part of the hair shaft.
False- the shaft
Where do natural fibers come from?
animals, plants, minerals
What did John Joubert do?
Killed 3 children
If you see a razor shaved hair, draw what you think the tip of the hair looks like. Where would you assume this came from?
teacher check drawing- rememble a right triangle
maybe face
How were Atlanta Child Murders, a series of 28 fatalities, linked to Wayne Williams?
fibers found on the victims matched items in Williams possession
The average human scalp contains how many hairs?
A. 5,000
b. 100,000
c. 10,000
d.100
B. 100,000
You're looking under a microscope and observe fabric where strands of fiber are in random loops or lines. Is this synthetic or natural fabric?
natural
What piece of evidence helped lead to the conviction of John Joubert for murder?
unique rope
To match a head hair found at the scene of a crime, police will take _______________ hairs from the prime suspect.
50
Human Hair is spinous. True or false
False
If the medullary Index is .65 the hair most likely came from who?
an animal
You are looking at a piece of fabric in a microscope and they are arranged with parallel lines in an organized way, is this natural or synthetic fabric?
synthetic
Approximately 85-90% of your hair is in this stage of hair growth that lasts approximately three to five years.
Bonus: what stage of your hair is 2-5% of your hair in?
Anagen
Bonus: catagen
How can you tell a public hair from a hair on head?
Buckling (straight then kind of lumps out)
The bits of pigment found as granules in the cortex of a hair is called:
melanin
True or false:
5 million hair follicles, only two percent of which are on the head.
True
When fibers are transferred directly from victim to suspect or suspect to victim, this is called:
direct transfer
medulla
The rate of hair growth is important to know because it can help determine the last time hair was chemically treated. Human hair grows at which rate:
1.3cm per MONTH
Hair is considered what kind of evidence?
Class evidence
What are the 3 purposes mammals have hair?
protect from sunlight and dust, decrease friction, regulate body temperature
You have one single fiber for analysis, which test(s) would you perform?
infared spectroscopy
The transparent outer later of the hair follicle that is made of scales is called the:
cuticle