Forensics Hair Quiz

  1. What are the purposes/uses of hair on mammals?

  • Protect us from the cold 

  • Reproduce - look good to attract a mate 

  • Nose hair filter germs/ pollution 

  • Eyelashes protect from dust and sweat 

  • Assert authority, intimidation

  • Sun protection.

  • Campflage. 

  • Reduce friction for swimmers in the ocean.

  1. What are the parts of the microscope used for? 

 the diaphragm -controls the amount of light 

the rotating nosepiece - allows to roate between lens 

the lenses - how far/ close you can see and object 

the stage - holds the slide. 

  1. Where is nuclear DNA found in hair? Why is it useful?

Hair’s root can be used to identify an indivdual. 

  1. How is mtDNA useful? What part of the hair is it found in?

Hair shaft is useful in forensic analysis, particularly when nuclear DNA is degraded or scarce, due to its high copy number and maternal inheritance. 

  1. What is the cuticle pattern for humans? What does it look like?

Human hair features an imbricate cuticle pattern, characterized by overlapping, flat, and smooth scales that resemble roof tiles.

  1. What are two other cuticle patterns that are commonly found in animals other than humans? What do they look like?

coronal (crown-like) and spinous (petal-like). 

  1. What are the common medulla patterns found in humans and what do they look like?

 Absent, fragmented, or continuous,

  1. What is the purpose of the cuticle?

It protects the outer layer and shields the inner hair shaft from damage. 

  1. Where is pigment found in hair?

Cortex. 

  1. Which way do the cuticles scales point, to the root or to the tip?

Towards the tip of the hair. 

  1. What is neutron activation analysis? What can it tell us about the hair or the person?

It reveals trace elements and potentially linking individuals to a location or event 

  1. Why is hair a good option for looking for poisons or drugs?

Because drugs remain in strands of hair for months longer than they do in the bloodstream

  1. What is secondary transfer?

he transfer of a substance from one object or person to another, via an intermediate object or person

  1. Calculate the medullary index. Be able to show your work. Use a ruler.

Divide the diameter of the medulla by the diameter of the entire hair shaft  

0.33 or less = human hair 

0.5 or greater = animal hair

  1. Calculate the time it took for a piece of hair to grow or be able to tell how long ago a toxin was ingested. Be able to show your work. Use a ruler. The growth rates of hair will be given. 

Hair grows at a rate of half an inch per month so if the hair is 18 inches then you could find drugs consumed more than 3 years ago.