Midterm Review Criminalistics

Forensic Science is defined as __________.

Science in the service of the law.

Criminalists are mainly responsible for __________.

Body fluid identification.

One unit that criminalistics may overlap with is __________.

forensic biology

Physical evidence is defined as __________.

Any and all objects that can establish that a crime has or has not been committed and can link a crime and its victim or perpetrator.

The founding principle of forensic science is __________, and it is named after __________.

Locard’s exchange principle; Edmund Locard.

A crime scene is defined as __________.

The area immediately associated with a criminal act or any area where elements of a crime or physical evidence can be located.

Two types of crime scenes are __________ and __________.

Indoor and Underwater.

Chain of custody is defined as __________.

A record of continuity of possession of the evidence.

The ultimate trier of fact is __________.

The jury.

A known sample is __________, while a questioned sample is __________.

A sample with a confirmed origin; a sample with an unconfirmed origin.

Class characteristics are defined as __________.

A broad group into which something falls.

Individual characteristics are defined as __________.

Evidence that can be attributed to only one source or as small a group as possible.

The four types of trace evidence include __________.

Hairs, fibers, paint, glass, soil.

Trace evidence might not be probative if __________.

It lacks uniqueness or is too common.

The three growth stages of hair are __________, __________, and __________.

Anagen, Catagen, Telogen.

The growth stage most likely to yield hair suitable for nuclear DNA is __________.

Anagen stage.

Three trace collection methods are __________, __________, and __________.

Tape lifting, Vacuuming, Tweezing.

The two different types of fibers are __________ and __________.

Natural and Synthetic.

Presumptive tests indicate __________.

The possible presence of a specific substance.

Confirmatory tests indicate __________.

The definitive presence of a specific substance.

The two types of control tests are __________ and __________.

Positive control and Negative control.

The component of blood that contains DNA is __________.

White blood cells.

Before testing, blood stains are described as __________.

Red-brown stain.

The OT test for blood produces __________ color change for a positive result.

A bright blue.

Three animals that test positive on a HemaTrace card are __________, __________, and __________.

Humans, higher primates, ferrets.

To determine a positive on a HemaTrace card, we look at __________.

The control and test line.

An alternate light source (ALS) is used to determine __________.

Stains that can’t be seen with the naked eye.

The Acid Phosphatase (AP) test shows __________ when positive for semen.

A purple color.

The scientific name for skin cells is __________.

Epithelial cells.

An extraction negative is a test run without DNA to check for __________.

Contamination.

The enzyme we are testing for in saliva is __________.

Human alpha-amylase.

The protein we test for in urine is __________.

Tamm-Horsfall protein.

The name of the test for fecal material is __________, and a positive result indicates __________ color.

Edelman’s test; bright green.

Screening tests are for __________, __________, and __________.

Saliva, urine, and feces.

Four items found in a sexual assault evidence collection kit might include __________, __________, __________, and __________.

Buccal swab, vaginal swab, external genital swab, fingernail scraping/swab.

Y screening is used to detect __________, which helps identify male contributors in mixed DNA samples.

Male DNA.

The three important characteristics for analyzing blood stains are __________, __________, and __________.

Size, shape, and distribution.

The characteristic of blood that gives blood droplets their shape is __________.

Surface tension.

Blood spatter is defined as __________.

A blood stain created when a blood drop is pushed through the air by a force applied to the source of the blood.

The CSI effect is defined as __________.

The phenomenon where television shows create unrealistic expectations about forensic investigations.

Two different search techniques for crime scenes are __________ and __________.

Grid Search and Spiral Search.

The pencil analogy for hair shafts compares the shaft of the hair to __________ and the medulla to __________.

The wood of the pencil; the lead.

Antigen-antibody reactions occur when __________ and are used in tests like __________.

An antibody binds to a specific antigen; blood typing, HemaTrace, ELISA, and immunohistochemistry.

Passive bleeding includes __________, __________, and __________.

Drip stains, drip trails, accompanying drops.

Accumulation/Volume patterns consist of __________, __________, and __________.

Flow pattern, pool, saturation stain.

Contact patterns contain __________, __________, and __________.

Transfer stain, swipe pattern, wipe pattern.

Spatter stains include __________, __________, and __________.

Impact pattern, expiration patterns, projected pattern.

Other patterns may consist of __________, __________, and __________.

Altered stains, blood clots, perimeter stains.