Hair Structure
The outermost layer of the hair shaft
What is the cuticle?
True or False: Human hair usually has a continuous medulla.
False
The longest growth phase, involving active growth
What is anagen
The first step in processing a crime scene
What is securing the scene?
Explain the difference between a rough sketch and a finished sketch.
Rough sketch: hand-drawn at the scene, includes measurements/labels. Finished sketch: neat, scaled, may be done with software, includes legend and north arrow.
The part of the hair that contains pigment granules.
What is the cortex?
True or False: Hair can provide both class and individual evidence.
True
The resting/shedding phase of hair growth
What is telogen?
Main purpose of a crime scene sketch.
What is to show the exact location of evidence?
Mapping method that uses a straight line between two fixed points.
What is baseline?
The central core of a hair strand.
What is the medulla?
Feature most useful for determining species.
What is the cuticle pattern
The part of hair that can provide nuclear DNA
What is the root/follicle?
Why does scale matter in a final sketch?
To accurately show distances between reference points and evidence
What is the difference between baseline mapping and rectangular coordinate mapping?
Baseline uses one perpendicular measurement while rectangular uses two perpendicular measurements
A forensic analyst measures a medullary index of 0.65. What does this suggest about the hair’s origin?
It’s most likely from an animal, since >0.5 suggests non-human origin.
Which cuticle pattern is rare in humans but common in animals like cats?
What is spinous?
The part of hair that contains mitochondrial DNA.
What is the cortex (hair shaft)?
A permanent, fixed reference point in crime scene mapping.
What is a datum point?
The type of sketch that is hand-drawn and includes measurements.
What is a rough sketch?
How to tell the difference between human hair and animal hair
What is medullary index and cuticle pattern
True or False: Hair can be used to determine the exact age of a person.
False
Why does hair usually provide class evidence unless the follicle/root is present?
Because shaft features overlap among individuals, but root DNA can uniquely identify a person.
Information that must be included in a finished sketch (name at least 3).
What are scale, compass direction, case info, and legend?
A legend in a crime scene sketch is used for this.
What is explaining the symbols used in the drawing?