Forensic Science Exam 2

What are the 3 physical states of matter?

Solid, liquid, gas

What is density defined as?

Mass/Volume

What is the difference between tempered and laminated glass?

Tempered glass is glass that is strengthen by introducing stress through rapid heating and cooling of the glass surface.

Laminated glass is two sheets of ordinary glass bonded by a layer of plastic.

What is the difference between wavelength and frequency?

Wavelength is how far apart the waves are while frequency is how many waves pass a point in one second.

What is chromatography?

A technique used for separating the components of a mixture.

What’s the goal of chromatography?

Analyze a mixture and its components in relation to one another.

What is mass spectrometry?

Material enters a high-vacuum chamber where a beam of high-energy electrons is aimed at the sample molecule

What part of the mass spectronetry machine seperates the fragments by mass?

electric/magnetic field

TLC is best used as a _____ _____ for _____

Screening tool for drugs

What is retention factor in TLC?

The distance spot as move/distance solvent has moved

How do you calculate retention factor (rf) in TLC?

Measuring the baseline from the top line in mm and dividing by the distance traveled by the solvent

The fingerprint region on IR spectra is the _____ _____ that identifies _____

confirmatory region that identifies substances

What are cutting agents?

They are non-controlled compounds added to drugs to increase the appearance of amount or to enhance drug effects

What are the 2 types of cutting agents?

Diluents and Adulterants

What are diluent cutting agents?

compounds added to increase the quantity of powder for distribution

What are adulterant cutting agents?

compounds added to increased the effect of the drug

What foes the Marquis 2 color test scan for?

heroin, morphine, and most opium derivatives

What foes the Dillie-Koppanyi color test scan for?

barbiturates

What foes the Duquenois-Levine color test scan for?

marijuana

What foes the Van Urk color test scan for?

LSD

What foes the Scott Test color test scan for?

cocain

What color would the Marquis 2 test turn if positive?

purple

What color would the Dillie-Koppanyi test turn if positive?

violet-blue

What color would the Duquenois-Levine test turn if positive?

purple

What color would the Van Urk test turn if positive?

blue-purple

What color would the Scott Test test turn if positive?

blue

Under the controlled substances act, what are the schedules of classifications for controlled dangerous substances?

drugs potential for abuse, potential for physical dependence, psychological dependence, medical value

Whats a drug?

natural or synthetic substance that is used to product physiological or psychological effects in humans

Drug analysis on _____ is the only way to determine long-term drug abuse

hair

Whats a screening test?

A test that is nonspecific and preliminary in nature

Whats a confirmation test?

A single test that specifically identifies a substance

What is pharmacokinetics?

a specific branch of pharmacology that studies what the body does to a drug

What does ADME stand for?

absorption, distribution, metabolism, excretion

What are the 5 routes of administering drugs?

orally, contact, snorting, injection, inhalations

What does AFIS stand for?

Automated Fingerprint Identification System

What are the 3 main fingerprint patterns?

loop, whorl, arch

How common is a Whorl pattern?

30%

How common is a loop pattern?

65%

How common is an arch pattern?

5%

What are the 2 premises surrounding the basis of fingerprint identification?

uniqueness and persistence

Whats a latent print?

A print that requires physical or chemical processing techniques to see it

Whats a patent print?

Visible prints left in a substance

What are plastic prints?

Visible 3D reproduction of the friction ridge skin observed in soft surfaces

What is a Level 1 fingerprint classification detail?

Pattern type

What is a Level 2 fingerprint classification detail?

Unique minutia

What is a Level 3 fingerprint classification detail?

Details of the shapes of the ridges

What fingerprint classification levels can be used for identification?

Level 2 and 3

What is nonporous evidence?

print residue sits on top of the surface

What is porous evidence?

print residue absorbs into the surface

Techniques used for nonporous evidence?

visual examination, cyanoacrylate fuming, fingerprint powder

Techniques used for porous evidence?

visual examination, ninhydrin

What are the 2-variables required to develop latent prints in superglue fuming chambers?

Heat and humidity

Who is the “Father of Fingerprints”?

Francis Galton

What is the Physiology of the Friction Ridge Skin?

Friction ridge skin lines the palms of the hands and bottoms of the feet. They are lined with sweat pores that secrete 98% water and other organic/inorganic compounds.

What dose ACE-V stand for?

Analysus, comparison, evaluation, vertification

The choice of fingerprint powders is based on what?

The contrast it can provide

What is a positive impression?

when outsole transfers substance onto a surface

What is a negative impression?

when outsole REMOVES substance from a surface

What is a dry-origin impression?

when outsole and surface are dry at time of impression

What is a wet-origin impression?

when outsole and surface are wet at the time of the impression

Whats a 2D impression?

transfer (or removal) of a substance from (or to) the outsole onto a surface and has length and width

Whats a 3D impression?

when an outsole deforms a substrate and has length, width and DEPT

For an examination quality photograph what is required?

Tripod, Film plane parallel, Bureau scale (L shaped), Oblique lighting

What are class characteristics of footwear?

design, brand, model

What could be individualizing footwear characteristics?

RAC’s like cuts or holes

Nevet attempt to fit a suspected ____ into the tool mark at a crime scene

tool

What are the 3 techniques used to chemically enhance bloody footwear impressions?

LCV, amido black, Hungarian red

What are the methods of recovering 2D impressions?

electrostatic dust lift, gel lifts, adhesive lifts

What are the methods of recovering 3D impressions?

dental stone cast and casting in snow

What are the common physical properties used to characterize glass?

color, thickness, density

What is refraction?

When light bends after passing through one material to another

What is dispersion?

The separation of light into its component wavelengths of visible light

Gamma rays have shorter ____ and higher _____

frequencies, wavelengths

From left to right, what is the order of the electromagnetic spectrum?

gamma rays, x-rays, UV, visible light, infrared, radio waves

As you go from the gamma rays to radio waves, the wavelength is getting _____ and getting lower____

longer, energy

What is the 4R rule?

Ridge lines on Radical fractures are at Right angles to the Rear

How can you tell the entry vs. exit on glass for bullets?

on entry side it is smoother than the exit side and the 2 fracture types

What are the 2 types of glass fractures?

Radial and concentric

Whats a radial glass fracture?

crack in glass that extends outward

whats a concentric fracture?

crack in glass that forms a rough circle around the point of impact