Chapter 3 Review Questions

All types of hair on the body are structurally the same and are involved with temperature regulation.

False, Hair are living structures

Today, all forms of hair evidence are considered to be of little value in crime-scene investigations.

False, they aren't considered little of value

Summarize how to correctly collect hair evidence from a crime scene.

If hair is firmly attached to clothing -Leave hairs intact; -Diagram and note the exact location of the of the adhering hair; -Photograph the hair; and -Package clothing (if dry) with attached hair. If hair is not firmly attached: -Photograph first in situ (natural environment as found at the scene); and -Use clean forceps to place hair into a small box or glass vial. -Once in the lab, the hair can be removed by plucking, shaking, and scraping surfaces. It can also be collected by placing clear tape over a surface so that the hair adheres to it and then transferring to acetate film before packaging. When surfaces are large, they can be vacuumed.

Summarize why forensic investigations compare an isotope analysis of someone's hair with the isotope signature of different locations.

Many water supplies have unique isotopic signatures that are captured in hair.

The period when hair is naturally shed is called the ____ Stage

Telogen

Hair can provide clues about someone's ancestry.

True

Technological advances such as chromatography and IRMS have improved the validity and reliability of hair analysis due to its objective analysis.

True

Which of the following characteristics is commonly found in Asian hair?

black medulla

Hair can be used to determine

diet, drug habits, and geographic history

Which part(s) of a hair can be analyzed for nuclear DNA?

follicle

Animal hair can be distinguished from human hair because animal hair

has a greater medullary index and more variation in the cuticle patterns

Human hair has which type of cuticle pattern

imbricate

Microscopic hair analysis

is used to exclude a suspect

Which factors are used to calculate the medullary index of the hair?

width of medulla and the width of the hair

Although variations can occur, which of the following best describes European hair?

straight or wavy with evenly distributed granules

Describe the structure of hair. Include in your answer the terms follicle, medulla, cortex, and cuticle.

the hair consists of 2 parts a follicle and a shaft. a follicle is a network of blood vessels that supply nutrients. the hair shaft is made up of 3 layers, the inner layer medulla, a cortex, and an outer cuticle. the cuticle is the outer coating composed of overlapping scales. the cortex is a protein-rich structure containing pigments. the medulla is the central core and it may be absent