Final exam study guide

Question 1

Individual evidence

Answer 1

Links to one unique source human/object

Question 2

Locard’s principle

Answer 2

“Every contact leaves a trace”

And also known as trace evidence.

Question 3

Physical evidence

Answer 3

Tangible items

Question 4

Probative value

Answer 4

The ability to prove something that is material to a crime

Question 5

Physical evidence examples

Answer 5

Fibers, fingerprints, glass, hair, Blood

Question 6

Class evidence

Answer 6

Can be linked to a group of people or objects.

Question 7

Primary/Secondary crime scene

Answer 7

Primary: the original location of CRIME or evidence.
Secondary: an alternative location where additional information may be found.

Question 8

Chain of Custody

Answer 8

The movement and location of physical evidence from the time it is obtained until the time it is presented in court.

Question 9

Packaging Evidence (Blood evidence, Fingerprints)

Answer 9

Each item must be collected in separate container or package and label it.
Material must not be put into an airtight bag

Question 10

Presumptive test

Answer 10

Is an analysis of a sample which establishes either: the sample is definitely not a certain substance or the sample is probably a substance.

Question 11

Confirmatory Test

Answer 11

Can help determine what the substance is: Limitations is that it could be wrong.

Question 12

BAC

Answer 12

Blood alcohol content:
BAC(girl)=(0.085) ( oz)(%) / Weight
BAC(boy)=(0.071)

Question 13

Find the BAC of a women who drinks three 5-ounce glasses of wine. Her weight is 135 pounds and the wince is 9% alcohol.

Answer 13

BAC=(0.085)(15)(9)/135

BAC=0.085 (answer)

Question 14

What is the proof of a type of liquor that causes a 142 pound man to have a BAC of 0.075 after consuming six one-ounce shots?

Answer 14

0.075=(0.071)(6)(%) / 142
10.65=0.426X
X=25%
Double 25 and it equals 50 proof(the answer)

Question 15

Positive control

Answer 15

Known blood will cause the color to appear (solutions are working)

Question 16

Negative control

Answer 16

Absence of blood - no appearance of color-showing no contamination

Question 17

Preciptin Test

Answer 17

Helps determine if it’s Human blood or animal blood

Question 18

Drug Metabolism

Answer 18

Is the removal of drugs from the body once they have preferred their function.

Question 19

Enzymes

Answer 19

Less active enzymes can lead to drug toxicity

Question 20

Alcohol

Answer 20

Ethanol

Question 21

Alcohol is absorbed

Answer 21

• 20% in stomach and 80% small intestines
• Average rate of removal is 0.015 percent per hour
• Most of metabolism takes place on the liver

Question 22

Why is Alcohol easily absorbed?

Answer 22

Due to it’s ease of dissolution in water
Alcohol is hydrophilic (attracted to water) muscles have water and fat doesn’t which is the reason why women have a higher BCC rate than men because men have more muscles.

Question 23

How does breathalyzer work?

Answer 23

Determines ethanol in breath, since alcohol is excreted in sweat, urine, and breath.

Question 24

What class is Narcotic placed in? And give an example of one?

Answer 24

Cocaine, Heroin
(Morphines)
Class A

Question 25

What class is stimulant? Example?

Answer 25

-Increases brain activity -caffeine, nicotine,ecstasy Class C

Question 26

What class is hallucinogen, example?

Answer 26

LSD, PCP | Class B

Question 27

What class is depressants? Example

Answer 27

Class B Amphetamines Opiod Barbiturates

Question 28

What is chromatography?

Answer 28

A technique to separate mixtures into their components

Question 29

Retention factor: Rf

Answer 29

Rf= distance component moves/ distance solvent moves

Question 30

What is a stationary phase?

Answer 30

Paper

Question 31

What is the mobile phase?

Answer 31

liquid solvent

Question 32

Development system

Answer 32

Making invisible spots visible

Question 33

Chronic exposure

Answer 33

Large amounts taken over a period of time

Question 34

Acute toxicity

Answer 34

One dose taken/given that is large enough to cause death

Question 35

LD50

Answer 35

Is the amount of toxin that will kill half of the test population Unit-Mg/kg 2.2lb=1kg Mg poison / kg body mass 1mg/kg x 82kg= 82 mg lethal dose

Question 36

Passive bloodstain

Answer 36

Flow pattern-from a moving surface

Question 37

Projected bloodstain

Answer 37

Low velocity- is a big spatter(large bloodstain) (Gunshot wound) High velocity- tiny spatters Some form of energy has been transferred to a blood source

Question 38

Transfer bloodstain

Answer 38

Example: a shoe print | An object with blood on it comes an contact with an object or surface that doesn't have blood on it

Question 39

Rh factor

Answer 39

Rh+ means that the factor is present | Rh- means that the factor is absent

Question 40

Antigens and Antibodies

Answer 40

Each blood type has antibodies to protect against the wrong type of antigen Type A has A antigen Type B has B antigen Antigen surround the red blood cell

Question 41

Blood components

Answer 41

Plasma- the liquid part of fhe blood 90% water 10%metabolites(waste, salts, ions, proteins) Cells-erythrocytes,leukocyte, platelets

Question 42

Latent fingerprint

Answer 42

Latent prints are impressions produced by the friction ridges, om human fingers, palms, and soles of the feet. Examiners analyze and compare latent prints to known prints of individuals in an effort to make identification or exclusions

Question 43

Patent fingerprints

Answer 43

Patent fingerprints, Can be made by ink, grease , dirt , this type of fingerprint is easily visible to the human eye.

Question 44

Plastic fingerprints

Answer 44

Are three dimensional impressions and can be made by pressing your finger in fresh paint, wax or soap.