Hair writing Essay
My name is Jaclyn and I am here to talk about hair components and how they are examined. I will go step by step to insure that everyone knows what makes up hair, how a hair sample is analyzed and why the crime scene hair evidence is a match to the suspect here today.
I will be talking about certain terms that are in the diagram above such as the shaft, follicle, root, bulb, cuticle, cortex and medulla. . The bulb is at the base of the hair and includes different layers of cells that extend through the hair follicle. The hair follicle is the structure that hair grows out of. The hair root is the part of the hair below the surface of the skin.
The hair shaft is the visible part of the hair that is seen through the skin. The hair shaft is made up of three parts which are the cuticle, cortex and medulla. The cuticle is the outer covering of the hair and inside of the cuticle is the cortex. The cortex has the pigment that gives hair its color. The medulla is the part of the hair that appears as a central canal running through the hair.The medulla allows a a hair to be classified as a human or animal sample.
There are four different types of medullas which are fragmented, interrupted, continuous or absent. When analyzing hair macroscopically you should look at the length, color, shaper (straight or wavy) and whether the follicle tissue is present or not. When analyzing hair microscopically you need to determine whether it is animal, human or synthetic. You can see whether the hair has been dyed or chemically treated.
Determining whether the hair was pulled out or cut can also be done.