The odds against a hair originating from another person are
about 4500 to 1
. The odds against two similar pubic hairs originating from two different individuals are about 800 to 1.
What remains the hair’s most characteristic feature?
| Question Answer | What remains the hair’s most characteristic forensic feature? DNA in root or follicle . | The scales that make up the cuticle point to what part of the hair? The tip. |
|---|
Why is hair not normally used for DNA typing?
Hair is considered
class evidence
when no source of DNA, such as follicle cells, is attached to the hair. Without DNA, hair can only be used as class evidence, to indicate color of hair and perhaps racial group. The hair providing class + individual evidence must have had follicle cells attached and therefore, DNA.
Does every hair on a person’s head have the same medulla pattern?
DNA may be found in the hair root and can be used to determine individual characteristics. There is no way a hair can be individualized.
Only one medulla pattern type is found in human hair
.
Can the body area of a hair be determined why not how?
The body area from which a hair originated can be determined by
general morphology
. Length, shape, size, color, stiffness, curliness, and microscopic appearance all contribute to the determination of body area. Pigmentation and medullar appearance also influence body area identification.
Which part of the hair is most rich in DNA?
The hair follicle at the base of human hairs
contains cellular material rich in DNA.
Can we tell if a hair was forcibly removed?
Is it possible to determine if hair was forcibly removed from the body? Yes,
a close examination of the hair root may
tell you whether the hair has fallen out or has been pulled out of the skin. … Head hair has a smaller diameter than other body hair and is more evenly colored.
Which feature of hair is most important in making a species identification?
At the centre of the hair shaft is
the medulla
, which is also valuable for species identification. Animals’ medullary index (ratio of the medulla’s diameter relative to the shaft’s diameter) is greater than humans’. Humans have a medullary index of less than 1/3 while the medullary index of animals is greater than 1/3.
What are the 4 medulla patterns?
Absent, Fragmental and Continuous
. In the Present Study medulla has been classified into Absent, Fragmented, Discontinuous and Continuous types (Photo attached).
What are 5 ways of collecting hair evidence?
- Visual collection. On some surfaces, hairs and fibers can be seen with the naked eye.
- Tape lifting. Trace tapes are available for the collection of trace hair and fiber evidence.
- Vacuuming.
How accurate is hair DNA testing?
A paternity test using hair done with the right hairs is not the best possible paternity test you can do. On average,
the success rate is around 60%
which means that the chances of extracting enough DNA for the test to be concluded are not exactly very high.
What kind of DNA is in the root of a hair?
Fragmented Nuclear DNA
Is the Predominant Genetic Material in Human Hair Shafts.
What is the most important part of the hair?
The follicle
is the essential unit for the generation of hair. The hair shaft consists of a cortex and cuticle cells, and a medulla for some types of hairs. Hair follicle has a continuous growth and rest sequence named hair cycle.
What type of evidence is being overlooked the most?
Footwear Impressions
.
Footwear and tire impressions
are perhaps the most overlooked evidence at a crime scene. When impressions are collected it is possible that identifications can be made linking a suspect or vehicle to the crime.
What is the deepest layer of hair?
The medulla
– the deepest layer of the hair shaft, only seen in large and thick hairs. The cortex – the middle layer of the hair shaft which provides the strength, colour and texture of a hair fibre. The cuticle – the outer layer of the hair shaft is thin and colourless. It serves as protection to the cortex.
How are head hairs different from other hair on the human body?
Hair on the head is different from hair on other parts of the body (more on that in a minute), but it actually all grows out to a specific length. It’s thought that these lengths are largely
determined by your genes
. … “The longer the anagen phase, the longer the hair will grow.”
