Exam 2 Forensic Chemistry
What are some common natural drugs?
-Morphine, codeine from opium poppy -marijuana -cocaine -caffeine -aspirin (willow bark)
What are narcotics?
-Narcotics mean "numbness" or "deadening" -they are analgesics, they relieve pain by depressing actions done by the CNS such as blood pressure, pulse rate, and breathing rate. -narcotics induce sleep
What are the non-drug factors that play a role in drug dependence?
-personal characteristics of the user -expectations about the drug experience -society's attitude and response to a drug
In order for a criminalist to determine whether a suspected stain is semen and not derived from contraceptive creams, vaginal secretions, or fruit juices, an acid phosphatase test reaction time of less than _____ seconds is expected.
30
An examiner observing the presence of motile sperm from vaginal samples taken from a victim can reasonably conclude that intercourse had most likely occurred within what time frame?
6 hours
Greiss Test
A chemical test used to examine patterns of gunpowder residues around bullet holes
firearms identification
A discipline primarily concerned with determining whether a bullet or cartridge was fired by a particular weapon.
narcotic
A drug that induces sleep and depresses vital body functions such as blood pressure, pulse rate, and breathing rate.
x-ray
A high-energy, short-wavelength form of electromagnetic radiation.
screening test
A preliminary test used to reduce the number of possible identities of an unknown substance.
antibody
A protein in the blood serum that destroys or inactivates a specific antigen.
short tandem repeat (STR)
A region of a DNA molecule that contains short segments of three to seven repeating base pairs.
nucleotide
A repeating unit of DNA consisting of one of four bases—adenine, guanine, cytosine, or thymine—attached to a phosphate-sugar group.
confirmation
A single test that specifically identifies a substance.
hallucinogen
A substance that induces changes in normal thought processes, perceptions, and moods.
analgesic
A substance that lessens or eliminates pain.
depressant
A substance that slows down, or depresses, the functions of the central nervous system.
stimulant
A substance that speeds up, or stimulates, the activity of the central nervous system.
antigen
A substance, usually a protein, that stimulates the body to produce antibodies against it.
buccal swab
A swab of the inner portion of the cheek; performed to collect cells for use in determining the DNA profile of an individual.
polymerase chain reaction (PCR)
A technique for replicating or copying a portion of a DNA strand outside a living cell.
multiplexing
A technique that simultaneously detects more than one DNA marker in a single analysis.
microcrystalline test
A test that identifies a specific substance based on the color and shape of crystals formed when the substance is mixed with specific reagents.
chromosome
A threadlike structure in the cell nucleus composed of DNA, along which the genes are located.
What is the clumping-together of red blood cells because of an antibody?
Agglutination
Which of the following drugs is said to have a high risk for psychological dependence?
Alcohol
oligospermia
An abnormally low sperm count.
spectrophotometry
An analytical method for identifying a substance by its selective absorption of different wavelengths of light.
ion
An atom or molecule bearing a positive or negative charge.
acid phosphatase
An enzyme found in high concentrations in semen.
choke
An interior constriction placed at or near the muzzle end of a shotgun's barrel to control shot dispersion.
allele
Any of several alternative forms of a gene located at the same point on a particular pair of chromosomes.
chromatography
Any of several analytical techniques for separating organic mixtures into their components by attraction to a stationary phase while being propelled by a moving phase.
antiserum
Blood serum that contains specific antibodies.
Which type of drug includes substances such as GHB and Ecstasy?
Club drugs
Which of the following narcotics is said to have a low psychological dependence risk?
Codeine
visible light
Colored light ranging from red to violet in the electromagnetic spectrum.
touch DNA
DNA from skin cells transferred onto the surface of an object by simple contact.
What was the computerized firearms database operated by the FBI in the early 1990s?
DRUGFIRE
Which of the following color screening tests help to determine the presence of marijuana?
Duquenois-Levine
What are some common synthetic drugs?
Fentanyl, diazepam, LSD, bath salts
low copy number
Fewer than eighteen DNA-bearing cells.
In order to make a casting of a shoe print found in the dirt at a crime scene, investigators would likely use what type of material?
Gypsum (dental stone)
Phencyclidine is considered which type of drug?
Hallucinogen
Heterozygous
Having two different allelic genes on two corresponding positions on a pair of chromosomes.
Homozygous
Having two identical allelic genes on two corresponding positions on a pair of chromosomes.
What is a semi-synthetic drug?
Heroin -Made by heating morphone and acetic anhydride in 1874 by CR Wright
In the early 1990s, the Bureau of Alcohol, Tobacco, Firearms, and Explosives (ATF) utilized the _____ in analyzing bullet and cartridge evidence.
IBIS
Under the federal Controlled Substances Act, a Schedule V substance can be stored where?
In a secured storage area
ultraviolet
Invisible long frequencies of light beyond violet in the visible spectrum.
infrared
Invisible short frequencies of light before red in the visible spectrum.
Which of the following is considered a color test for blood?
Kastle-Meyer
Which one of the following color tests can be used to determine the presence of heroin or methamphetamines?
Marquis
When an examiner wants to "lift" an impression print possibly made by a boot on a tile floor covered in dust, they likely would use _____.
Mylar (used along with electrostatic lifting)
Which system, with more than one and a half million images, is utilized by more than 200 law enforcement agencies around the world?
NIBIN
Which type of drug is known for inducing sleep and reducing bodily functions such as blood pressure, pulse, and breathing?
Narcotic
picogram
One-trillionth of a gram or 0.000000000001 gram.
The p30 protein, also known as _____, is used in testing for seminal fluids.
PSA (prostate-specific antigen)
How can an investigator aid a chemist in reducing the time it takes to determine a drug's identity?
Provide any background information about the substance
An investigator seeking to determine a brand of footwear from a collected impression might utilize what database system?
SICAR (shoeprint image capture and retrieval)
Under the federal Controlled Substances Act, _____ drugs have a high potential for abuse, have no currently accepted medical use in the United States, and/or lack accepted safety for use in treatment under medical supervision.
Schedule I
Anabolic steroids fall into which classification under the federal Controlled Substances Act?
Schedule III
mitochondria
Small structures outside the nucleus that supply energy to a cell.
_____ is an analytical method for identifying a substance by its selective absorption of different light wavelengths.
Spectrophotometry
substrate controls
Surface material close to areas where physical evidence has been deposited.
anabolic steroids
Synthetic compounds, chemically related to the male sex hormone testosterone, that are used to promote muscle growth.
aspermia
The absence of sperm; sterility in males.
gene
The basic unit of heredity, consisting of a DNA segment located on a chromosome.
refraction
The bending of a light wave caused by a change in its velocity.
zygote
The cell arising from the union of an egg and a sperm cell.
agglutination
The clumping together of red blood cells by the action of an antibody.
psychological dependence
The conditioned use of a drug caused by underlying emotional needs.
Grooves
The cut or low-lying portions between the lands in a rifled bore.
caliber
The diameter of the bore of a rifled firearm, usually expressed in hundredths of an inch or millimeters—for example, .22 caliber and 9 millimeter.
wavelength
The distance between crests of adjacent waves.
electromagnetic spectrum
The entire range of radiation energy from the most energetic cosmic rays to the least energetic radio waves.
egg
The female reproductive cell.
x chromosome
The female sex chromosome.
plasma
The fluid portion of unclotted blood.
Bore
The interior of a firearm barrel.
serum
The liquid that separates from the blood when a clot is formed.
sperm
The male reproductive cell.
y chromosome
The male sex chromosome.
ejector
The mechanism in a firearm that throws the cartridge or fired case from the firearm.
extractor
The mechanism in a firearm that withdraws a cartridge or fired case from the chamber.
deoxyribonucleic acid (DNA)
The molecules that carry the body's genetic information.
frequency
The number of waves that pass a given point per unit of time.
epithelial cell
The outer layer of skin cells.
locus
The physical location of a gene on a chromosome.
physical dependence
The physiological need for a drug brought about by its regular use and characterized by withdrawal sickness when administration of the drug is abruptly stopped.
distance determination
The process of determining the distance between the firearm and a target, usually based on the distribution of powder patterns or the spread of a shot pattern.
lands
The raised portion between the grooves in a rifled bore.
breech face mark
The rear part of a firearm barrel.
dispersion
The separation of light into its component wavelengths.
gauge
The size designation of a shotgun; originally the number of lead balls with the same diameter as the barrel that would make a pound. The only exception is the .410 shotgun, in which bore size is 0.41 inch.
rifling
The spiral grooves formed in the bore of a firearm barrel that impart spin to the projectile when it is fired.
What is the least intrusive method for obtaining a DNA reference sample?
a buccal swab
To avoid the growth of bacteria and fungi, biological evidence should be packaged in _____.
a paper bag
What is used to reduce the number of possible identities of an unknown substance?
a screening test
What is a drug?
a substance, natural or synthetic, which can produce psychological or physiological effects in humans or other higher order animals
A criminalist might utilize a mapping technique to search large pieces of fabric for the presence of the enzyme _____, which is found in high concentrations in seminal fluid.
acid phosphatase
When collecting and preserving drug evidence, if there is concern over the volatility of a substance, what should be used to prevent evaporation?
an airtight container
A solution of hydrochloric acid, copper chloride, and water works well as _____ for steel surfaces.
an etching reagent
When developing immunoassay testing for drugs, the prepared drug-protein complex acts as a/an _____, stimulating the production of antibodies.
antigen
Currently under feasibility consideration is a _____ system, in which firearms would be test-fired prior to their sale to the public, and images from the markings on bullets and cartridges would be stored in an accessible database.
ballistic fingerprinting
A ballistics examiner might use a firearm's _____ to compare and contrast markings on a firearm's shell cartridge with discharged cartridges found at a crime-scene.
breech face mark
Wrapping the _____ in tissue paper and placing it into an evidence envelope before it is shipped to the crime laboratory is recommended.
bullet
.22 or 9mm are examples of a gun's _____.
caliber
What influences the pattern, speed, and distance of pellets from a shotgun?
choke
Genes are located on which threadlike structure in the cell nucleus?
chromosome
Examination of tool marks commonly reveals important _____, which give a better picture of the size and shape of the tool used.
class characteristics
Which of the following drugs is said to have a high risk for psychological dependence but a low risk for physical dependence?
cocaine
Compare the strengths of codeine, morphine, heroin, and fentanyl
codeine: 0.2x morphine: 1x Heroin: 2x Fentanyl: 100x
To answer the question of whether or not a discovered stain might be blood, a criminalist might rely upon _____ tests that require the observation of hemoglobin possessing peroxidase-like activity.
color
What can occur when extraneous DNA is introduced onto an item during the collection process, or when evidence items are incorrectly placed in contact with one another during packaging?
contamination
Alcohol is considered which type of drug?
depressant
Alcohol, phenobarbital, diazepam, and aerosol gas propellants are all grouped together under which type of drug?
depressants
Which gunpowder-residue testing process can give conflicting positive reactions with fertilizer, cosmetics, urine, and tobacco?
dermal nitrate
In examining gunpowder evidence, investigators may utilize _____ to differentiate between a suicide and a homicide.
distance determination
What is the outer layer of skin cells, often found inside a glove or on the handle of a weapon located at the scene of a crime?
epithelial cells
Which firearm mechanism is responsible for withdrawing a cartridge or fired case from the chamber of a firearm?
extractor
For a stain already determined to be blood, a criminalist might use a _____ test to determine the species of the blood, which employs the use of a natural polymer known as "agar."
gel diffusion
What is a microscopic unit of heredity that controls the development of a specific characteristic in a new individual?
gene
If a gene pair consists of two matching genes, it is said to be _____.
homozygous
In linking serial crimes to one another, investigators make use of CODIS to match crime-scene DNA evidence to _____.
known offenders
When an investigator discovers a heavy concentration of residue and scorch marks around the a bullet's entrance hole, it was likely fired _____ from the victim.
less than 1 inch
Under the Federal Controlled Substances Act, which of the following drugs would be considered to have a high potential for abuse and no currently accepted medical use in the United States?
marijuana
When a criminalist is testing for blood, what type of test are they performing if they use a Takayama?
microcrystalline
A forensic scientist looking to identify the badly charred remains of a bombing attack victim would most likely use _____.
mitochondrial DNA
What is found outside the nucleus of a cell and is inherited solely from the mother?
mitochondrial DNA
Which of the following drugs would be considered an opiate?
morphine
What process is the most efficient way to copy short tandem repeats (STRs)?
multiplexing
Trace evidence, such as _____, can prove very valuable in the analysis of tool marks left in the forcible entry into a structure.
paint chips
When a drug user keeps using a drug to avoid withdrawal symptoms, they are likely dealing with _____.
physical dependence
When analyzing the fluid portion of unclotted blood, known as _____, we might anticipate finding solid materials suspended in it.
plasma
What is a technique for replicating or copying a portion of a DNA strand outside of a living cell?
polymerase chain reaction
DNA _____ are enzymes that assemble a new DNA strand in the proper base sequence determined by the original DNA strand.
polymerases
Contrary to television shows, an investigator should avoid retrieving a firearm by sticking a pencil in the barrel so that the _____ are not disturbed.
powder deposits
Color testing should be considered _____ in nature.
presumptive
When a drug user is conditioned to use because of underlying emotional needs, it is said to be _____.
psychological dependence
A firearm's _____ refers to the process of creating an inner surface pattern that causes a projectile to spin when it is fired.
rifling
What is the most important consideration in handling a recovered weapon at the crime scene?
safety
When collecting _______ evidence from a sexual assault victim, it is recommended to use a swab moistened with distilled water on a suspected area, followed by a second dry swab rotated over the same area and packaged together.
saliva
Which of the following is an example of a screening test that a field officer could easily use to detect an illicit substance?
scott test
A fabric stain that appears to have a whitish, crusty appearance is most likely to be a _____ stain
seminal
The jury in the O.J. Simpson case did not hear valuable _____ evidence because the expert analysis was significantly time-consuming due to the intricately rare details of the comparison.
shoe print
When mapping DNA, if a criminalist observes a/an _____, they know that the sex of the person is male.
short chromosome
As a means of distinguishing one individual from another through DNA typing, geneticists focus on _____, which are non-coding regions of the DNA.
short tandem repeats
What type of handgun requires cartridges to be loaded and removed one by one from a small "gate" at the back of the gun?
solid-frame revolver
Serial numbers are usually _____ a metal body or frame or on a metal plate.
stamped on
Which of the following procedures should be performed by a medical professional to collect evidence from a victim related to a sexual assault that included touching, kissing, and licking, but no form of penetration?
swabbing of body areas
Many states have modeled their own drug control laws after _____.
the Controlled Substances Act
In using common sense, a crime investigator may want to transport any drugs collected from the scene to the lab in _____ to prevent evidence loss or cross-contamination related to the preservation of drug evidence.
the original container
When a firearm is recovered underwater, it should be transported to the crime laboratory in a receptacle containing _____.
the same water
What is the evidentiary purpose of taking a urine test from a sexual assault victim quickly after the suspected occurrence?
to determine the presence of rohypnol or GHB
Which comparisons are difficult to replicate with accuracy in the laboratory, and require a series of samples at various angles and pressures?
took marks
When investigating a burglary, an investigator likely will take note of any _____ located within the doorframe of the suspected entry point.
tool marks