Hair and Fiber Test Questions and Answers With Verified Solutions 2025
Hair as evidence/ how it is helpful - ✔✔Human hair is one of the most frequently found pieces of
evidence at the scene of a violent crime. It can provide a link between the criminal and the crime.
From hair one can determine - ✔✔-If the source is human or animal
-Race (sometimes)
-Origin of the location on the source's body
-Whether the hair was forcibly removed
-If the hair has been treated with chemicals
-If drugs have been ingested
Cuticle - ✔✔outside covering, made of overlapping scales
Cortex - ✔✔inner layer made of keratin and imbedded with pigment; also contains air sacs called
cortical fusi
Medulla - ✔✔inside layer running down the center of the cortex
Scales - ✔✔cover the cuticle (outermost layer of hair)
The scales point toward the tip of the hair. Scales differ among species of animals and are named based
on their appearance.
3 basic types of scale patterns- coronal, spinous, imbricate
Cuticle scales in humans - ✔✔commonly are flattened and narrow -imbricate
Cuticle scales in animals - ✔✔tend to resemble petals- spinous
or they give the appearance of a stack of crowns -coronal
, Cortex- gives hair its shape and has two major characteristics which are - ✔✔- Melanin—pigment
granules that give hair its color
- Cortical fusi—air spaces, usually found near the root but may be found throughout the hair shaft
Medulla is the hair core that is not always visible. The medulla comes in different types and patterns -
✔✔continuous, fragmented, or absent
Medullary index - ✔✔- Determined by measuring the diameter of the medulla and dividing it by the
diameter of the hair.
- Medullary Index for human hair is generally less than 1/3.
- For animal hair, it is usually greater than 1/2.
Pigmentation in animal VS human hair - ✔✔animal- denser towards the medulla
human- denser towards the cuticle
Aniaml hair can abruptly change colors in banded patterns
Medullary index in animal VS humans - ✔✔animals- the medulla is animal hair abruptly can change
colors in banded patterns.
nothing special abt humans
Questioned hairs must be accompanied by a decent amount of control samples and the control samples
must be - ✔✔-from victim
-from possible suspects
-from others who may have
-deposited hair at the scene
Control Sample
50 full-length hairs from all areas of scalp
Hair as evidence/ how it is helpful - ✔✔Human hair is one of the most frequently found pieces of
evidence at the scene of a violent crime. It can provide a link between the criminal and the crime.
From hair one can determine - ✔✔-If the source is human or animal
-Race (sometimes)
-Origin of the location on the source's body
-Whether the hair was forcibly removed
-If the hair has been treated with chemicals
-If drugs have been ingested
Cuticle - ✔✔outside covering, made of overlapping scales
Cortex - ✔✔inner layer made of keratin and imbedded with pigment; also contains air sacs called
cortical fusi
Medulla - ✔✔inside layer running down the center of the cortex
Scales - ✔✔cover the cuticle (outermost layer of hair)
The scales point toward the tip of the hair. Scales differ among species of animals and are named based
on their appearance.
3 basic types of scale patterns- coronal, spinous, imbricate
Cuticle scales in humans - ✔✔commonly are flattened and narrow -imbricate
Cuticle scales in animals - ✔✔tend to resemble petals- spinous
or they give the appearance of a stack of crowns -coronal
, Cortex- gives hair its shape and has two major characteristics which are - ✔✔- Melanin—pigment
granules that give hair its color
- Cortical fusi—air spaces, usually found near the root but may be found throughout the hair shaft
Medulla is the hair core that is not always visible. The medulla comes in different types and patterns -
✔✔continuous, fragmented, or absent
Medullary index - ✔✔- Determined by measuring the diameter of the medulla and dividing it by the
diameter of the hair.
- Medullary Index for human hair is generally less than 1/3.
- For animal hair, it is usually greater than 1/2.
Pigmentation in animal VS human hair - ✔✔animal- denser towards the medulla
human- denser towards the cuticle
Aniaml hair can abruptly change colors in banded patterns
Medullary index in animal VS humans - ✔✔animals- the medulla is animal hair abruptly can change
colors in banded patterns.
nothing special abt humans
Questioned hairs must be accompanied by a decent amount of control samples and the control samples
must be - ✔✔-from victim
-from possible suspects
-from others who may have
-deposited hair at the scene
Control Sample
50 full-length hairs from all areas of scalp
