Forensic Science 1-4

Front 1

Factors affecting observational skills?

Back 1

-alone or with a group or people

-number of people or animals in the area

-what type of activity is going on around you

-how much activity is occurring.

-Emotional state

Front 2

What % of eyewitness contributed to faulty convictions?

Back 2

87%

Front 3

Director of the worlds first forensic lab

Back 3

Dr. Edmond Locard

Front 4

Locard's Principles of Exchange

Back 4

When a person comes into contact with an object or another person, a cross transfer of physical evidence can occur

Front 5

What determines the extent of trace evidence transfer?

Back 5

Duration, intensity and nature

Front 6

What are two types of evidence

Back 6

Circumstantial and direct

Front 7

Circumstantial evidence?

Back 7

indirect evidence that can be used to imply a fact but that does not prove it.

Front 8

Direct Evidence?

Back 8

Firsthand observations such as eyewitness. This involves testimony of what a witness heard, saw or did. Another example: Confessions

Front 9

Circumstantial evidence

PHYSICAL EVIDENCE EX.

Back 9

Fingerprints, footprints, tool marks, weapons, bullets.

Front 10

Circumstantial evidence

BIOLOGICAL EVIDENCE EX.

Back 10

Blood, DNA, bodily fluids, hair , plants, pollen, natural fibers.

Front 11

Class Evidence

Back 11

Narrows an identity to a group of persons or things

Front 12

individual evidence

Back 12

narrows an identity to a single person or thing.

Front 13

Seven S's of crime scene investigation

Back 13

Securing the scene

separating the witnesses

scanning the scene

seeing the scene

sketching the scene

searching for evidence

securing and collecting evidence

Front 14

Triangulation

Back 14

mathematical method of calculating the location of an object from the locations of other objects

Front 15

4 examples of search patterns

Back 15

Grid, linear, quadrant/zone, spiral

Front 16

Evidence log should contain?

Back 16

case #

item inventory #

description of evidence

name of suspect

name of victim

date and time of recovery

signature of person recovering evidence

signature of witness present during collection

Front 17

datum point

Back 17

a permanent or fixed point. Ex. corner of building, tree. in which measurements can be taken from.

Front 18

Functions of hair

Back 18

1. Regulate body temperature

2. Reduce friction

3. Protect skin from sun.

4. Acts as a sense organ.

Front 19

what type of evidence is hair without a follicle?

Back 19

Class

Front 20

What needs to be present for DNA to be obtained from hair

Back 20

Follicle and Nuclear DNA

Front 21

What type of evidence is hair with a follicle and nuclear DNA

Back 21

Individual evidence

Front 22

Chemical tests on hair can reveal?

Ex. Gas chromatography

Back 22

identify and quantify drugs, toxins, heavy metals, and nutrient deficiencies

Front 23

Mitochondrial DNA

Back 23

present in hair shafts can reveal family relationships. M DNA is inherited from the mother and passed down

Front 24

What two parts does a hair consist of?

Back 24

Follicle, shaft

Front 25

Follicle

Back 25

a club shaped structure in the skin.

Cells that contain DNA

Blood vessels

Front 26

what protein is in the shaft?

Back 26

keratin

Front 27

What does keratin do?

Back 27

makes hair strong and flexible

Front 28

3 layers of hair

Back 28

Inner Medulla

Cuticle

Cortex

Front 29

six types of hair?

Back 29

head

eyebrows and eyelashes

beard and mustache

underarm

body

pubic

Front 30

3 stages of hair

Back 30

Anagen stage

Catagen stage

telogen stage

Front 31

Anagen stage

Back 31

first stage

lasts approx 1000 days

80%-90% of all human hair is in this stage

active growth phase

Front 32

catagen stage

Back 32

hair stops growing

follicle recedes as blood supply reduced

2% of all hair growth and development

Front 33

Telogen stage

Back 33

follicle is dormant

hairs easily lost

10%-18% of hair is in this stage

Front 34

how fast does hair grow?

Back 34

1.3 cm/ month

Front 35

human hair v animal hair

(differences)

Back 35

Pattern of pigmentation

medullary index

cuticle type

animal -index .5 or more

human- index .33 or less

Front 36

imbricate

Back 36

cuticle scales that are flattened and narrow

Front 37

why are fibers important?

Back 37

to create link between crime and suspect

Front 38

direct transfer?

Back 38

the passing or evidence from a victim to suspect of vice versa

Front 39

secondary transfer?

Back 39

fibers transferred from an object onto a person who then transfers it to another person

Front 40

how are fibers collected

Back 40

vacuum, tape, forceps, lint roller

Front 41

how to evaluate fibers without damaging them?

Back 41

polarizing light microscopy

infrared spectroscopy

microspectrophotometry

ultra violet light analysis

Front 42

two classes of fibers?

Back 42

natural

synthetic

Front 43

Where do natural fibers come from?

Back 43

animals

plants

minerals mined from the ground

Front 44

types of plant fibers?

Back 44

seed fibers

fruit fibers

stem fibers

leaf fibers

Front 45

how do fabrics differ?

Back 45

weave pattern

thread count