Warm-UpSeptember 23, 2014

Warm-UpSeptember 23, 2014

Draw and label the following parts of the hair shaft: medulla, cortex and cuticle.

Draw and label the following parts of the hair shaft: medulla, cortex and cuticle.

ObjectiveObjective

SWBAT differentiate between human and animal hair.

SWBAT differentiate between human and animal hair.

AgendaAgenda

1. DNA & Toxicology2. Atlanta Child Murders Documentary3. Human vs. Animal Hair4. Microscopy5. Exit Slip

1. DNA & Toxicology2. Atlanta Child Murders Documentary3. Human vs. Animal Hair4. Microscopy5. Exit Slip

Hair Analysis Lab

• Follow the directions and make sure that you draw the pictures and answer the questions on a separate sheet of paper.

DNA from Hair

Root contains nuclear DNA folicular tissue may be attached

containing DNA

Shaft contains abundant mitochondrial DNA,

inherited only from the mother typed by comparing relatives if no DNA

from the body is available ($$$)

Collection of Hair

Questioned hairs must be accompanied by an adequate number of control samples. 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 24 full-length pubic hairs

Hair Toxicology

Advantages: Easy to collect and store Is externally available Can provide information on the individual’s

history of drug use or of poisoning.

Collections must be taken from different locations on the body to get an accurate timeline.

Hair Toxicology Napoleon died in exile

in 1821. By analyzing his hair, some investigators suggest he was poisoned by the deliberate administration of arsenic; others suggest that it was vapors from the dyes in the wallpaper that did him in.

Atlanta Child Murders DocumentaryAtlanta Child Murders Documentary9. Where were many of the bodies dumped? 10. What did forensic scientist Larry Peterson find at the autopsy of a body that was found? 11. Who did police suspect was the serial killer in February of 1981 based on a tip they received? 12. What test cleared members of the Klan? 13. What was being collected from the victims clothing? 14. What happened when the bodies started appearing in the river and how did that affect the amount of evidence? 15. What suggested the bridge stake outs? 16. What happened on the last night of the bridge stake outs? 17. What did police find when they searched William’s station wagon?

9. Where were many of the bodies dumped? 10. What did forensic scientist Larry Peterson find at the autopsy of a body that was found? 11. Who did police suspect was the serial killer in February of 1981 based on a tip they received? 12. What test cleared members of the Klan? 13. What was being collected from the victims clothing? 14. What happened when the bodies started appearing in the river and how did that affect the amount of evidence? 15. What suggested the bridge stake outs? 16. What happened on the last night of the bridge stake outs? 17. What did police find when they searched William’s station wagon?

Animal vs. Human Hair:Color

Animal vs. Human Hair:Color

Human hairs are generally consistent in color and pigmentation throughout the length of the hair shaft, whereas animal hairs may exhibit radical color changes in a short distance, called banding.

Human hairs are generally consistent in color and pigmentation throughout the length of the hair shaft, whereas animal hairs may exhibit radical color changes in a short distance, called banding.

Human vs. Animal Hair: Medullary Index

Human vs. Animal Hair: Medullary Index

The medulla, when present in human hairs, is generally less than one-third the overall diameter of the hair shaft.

The medulla in animal hairs is normally continuous or interrupted, and it generally occupies an area of greater than one-half the overall diameter of the hair shaft.

The medulla, when present in human hairs, is generally less than one-third the overall diameter of the hair shaft.

The medulla in animal hairs is normally continuous or interrupted, and it generally occupies an area of greater than one-half the overall diameter of the hair shaft.

Human hair is imbricate (flattened) Animal hair varies by species, but

can be spinuous or coronal, as well as imbricate

Human hair is imbricate (flattened) Animal hair varies by species, but

can be spinuous or coronal, as well as imbricate

Human vs. Animal Hair: Cuticle

Human vs. Animal Hair: Cuticle

Human vs. Animal Hair:Tip

Human vs. Animal Hair:Tip

Scissor cut or razor cut implies the hair has been “groomed”. Many animals are not groomed so if you see a scissor cut tip or a razor cut tip it might be a clue that the type of hair you are looking at did not come from an animal.

Scissor cut or razor cut implies the hair has been “groomed”. Many animals are not groomed so if you see a scissor cut tip or a razor cut tip it might be a clue that the type of hair you are looking at did not come from an animal.

Human HairsHuman Hairs

Horse HairHorse Hair

Dog HairDog Hair

Cat HairCat Hair

Mouse HairMouse Hair

Rabbit HairRabbit Hair

Deer HairDeer Hair

Cow HairCow Hair

Pig HairPig Hair

Special Conditions of Hair

Special Conditions of Hair

The following slides show the ends of several different

species of hairs

The following slides show the ends of several different

species of hairs

Fallen Out HairsFallen Out Hairs

Natural TipNatural Tip

Pulled Out-By the RootPulled Out-By the Root

Broken-TornBroken-Torn

Cut HairCut Hair

Can you identify the animal hairs shown?Can you identify the animal hairs shown?

Think About It …

(1)In which samples are we viewing the cuticle? How do they compare?

(2) In which samples are we viewing the medulla? How do they compare?

(3) What characteristics can be used to identify hair samples?

Types of Animal Hairs - KeyTypes of Animal Hairs - Key

A B C D

E F

G

IH

Cat Horse Pig Human

Deer Dog RatRabbit Human

Comparison MicroscopeComparison Microscope

Allows the examiner to view the questioned and known hair together, side by side

Necessary to have an adequate number of known hairs that are representative of all its features when making a comparison

Allows the examiner to view the questioned and known hair together, side by side

Necessary to have an adequate number of known hairs that are representative of all its features when making a comparison

Issues with MicroscopesIssues with Microscopes

Subjective approach Dependent on skills and integrity

of the analyst

Subjective approach Dependent on skills and integrity

of the analyst

DNA AnalysisDNA Analysis

Study done on hair evidence of FBI between 1996 – 2000 and found that only 11% of hairs found a positive microscopic match

Now must hair evidence must be confirmed by DNA analysis

Study done on hair evidence of FBI between 1996 – 2000 and found that only 11% of hairs found a positive microscopic match

Now must hair evidence must be confirmed by DNA analysis

HomeworkHomework

Chapter 10 Review Questions, #15-20 due Wednesday

Chapter 10 Review Questions, #15-20 due Wednesday

Exit SlipSeptember 23, 2014

Exit SlipSeptember 23, 2014

1. Get out a mobile device or use one of the computers and go to m.socrative.com. You can also use one of the iPads that has the Socrative app. 2. When prompted, enter 417101 for the room number.QUESTION: What are characteristics used to determine the difference between human and animal hair?

1. Get out a mobile device or use one of the computers and go to m.socrative.com. You can also use one of the iPads that has the Socrative app. 2. When prompted, enter 417101 for the room number.QUESTION: What are characteristics used to determine the difference between human and animal hair?