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89 Cards in this Set
- Front
- Back
Who should certify that a body is dead? |
Medical examiner
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What does observing a crime scene involve? |
Initial walk through; plan of action
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What are the 4 search patterns of a crime scene? |
Grid, quadrant, spiral, line (strip)
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How do you decide which pattern to use? |
Size, location, and # of investigators
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How do you package evidence at a crime scene? |
Individually; new packaging
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What evidence can you not package immediately? Why? |
Wet objects; mold and mildew |
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Which two scientists were known for devising experimentation for blood types? |
Landsteiner and Lattes
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Who was responsible for courts acceptance of documents as scientific evidence? |
Albert Osborn
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What court case in 1923 set the "general acceptance" of scientific evidence? |
Fry vs US
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What are the roles of an expert witness? |
Establish credibility, render opinion, evaluate evidence
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What do forensic scientists use physical evidence for? |
Identification/comparison |
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What is identification used for? |
Determine physical/chemical identity |
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What is identification used for? |
Determine whether a common origin exists |
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What is the difference between individual characteristics and class characteristics? |
Class: group Individual: linked to one source |
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Give 2 examples of physical properties. |
Density, color, texture, odor |
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Give 2 examples of chemical properties. |
Flammability, reactivity |
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What is refraction? |
Bending of light from one medium to another |
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What can fracture patterns tell an investigator? |
Sequence of events, direction of impact, high or low velocity impact |
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What are the types of fracture patterns of glass? |
Soda lime: windows Soda lead: fine tableware Borosilicate: pyrex baking Silica: chemical ware Tempered: side windows |
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What are natural fibers? |
Made from animals/plants |
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List some examples of natural fibers. |
Cotton, wool, silk, hemp |
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What are synthetic fibers and what would an example be? |
Man made/altered: acetate, rayon, polyester |
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What type of fibers contain proteins? |
Animal |
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What three fibers dissolve in formic acid? |
Nylon, silk, acetate |
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When performing the sulfur test, what color precipitation should show a positive outcome? |
Black or dark gray |
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What is the only fabric to dissolve in acetate. |
Acetate |
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What are examples of mineral fibers? |
Asbestos, rock wool, fiberglass |
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What are examples of cellulose fibers? |
Cotton, rayon, cellulose acetate |
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How should you collect fiber evidence? |
Tape lifts, bag individually, removed fibers should be folded into a sheet of paper and stored in paper bag |
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How often does hair grow? |
1cm a month |
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What are the 3 layers of hair? |
Cuticle Cortex Medulla |
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Which layer has pigment granules? |
Cortex |
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Which layer is resistant to chemical decomposition? |
Cuticle |
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How can the medulla be classified? |
Stacked Continuous Absent Fragmented Interrupted |
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What type of medullas do animals usually have? |
Stacked, continuous, interrupted |
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What type of medullas do humans usually have? |
Continuous, Fragmented, Absent |
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What are the 3 stages of growth and how long do they last? |
Anagen: 5 years Catagen: 2-3 weeks Telogen: 2-6 months |
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What is the best stage for DNA comparison of hair? |
Anagen |
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If there is no nuclear DNA present, what type do scientists use? |
Mitochondrial DNA |
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When taking reference samples from the head, how many hairs do you need? |
50 full length |
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What is DNA made of? |
Nucleotides |
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What is the shape of falling blood? |
Round |
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What binds with blood types A, B, AB, and O? |
O |
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What does it mean if you have a + blood type? |
+Rh and A antigens |
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What are the 4 nitrogen bases? |
Adenine, thymine, cytosine, guanine |
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What test for blood produces a glowing light if blood is present? |
Luminol |
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What does it mean if the drops are small at a crime scene? |
More force |
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What are the 3 basic fingerprint pattern? |
W: 30-35% L: 60-65% |
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What are latent prints? |
Invisible prints made of secretions and oil |
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What are plastic prints? |
Visible prints made in a soft material |
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What are the components of latent prints? |
.5-1% solids, 99-99.5% water |
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What invention in China leads to developing firearms? |
Gun powder |
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What is the chemical composition of this invention? |
KNo3, charcoal, sulfur |
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What are two types of long guns? |
Rifles and shot guns |
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What is the difference between semi-automatic and fully automatic weapons? |
Semi: one bullet per trigger pull Fully: repeatedly as long as trigger is pressed |
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What is rifling? |
Spiral pattern of lands/grooves in a barrel
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What are lands and grooves? |
Lands: ridges Grooves: depressions |
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What is gunshot residue? |
Tiny particles of unburned powder and traces of smoke |
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How is the amount of GSR affected by distance? |
Distance up, GSR up |
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What are the 3 methods for engraving serial numbers? |
Dot matrix Laser engraving Stamping |
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When an individual removes a serial number, typically how many layers are removed? |
Usually top layer |
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How do you restore a serial number? |
Sand and polish surface, add acid, document |
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What chemical does an investigator test for when testing for GSR? |
Nitrates |
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What is the purpose of primer power? |
Initiates the explosion of the gun powder |
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What is the normal pH of a stomach? |
1-3 |
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What is an analgesic? |
Pain reliever |
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What does aspirin act as? |
Analgesic Anti-pyretics Anti-inflammatory |
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What is the active ingredient in Advil and aspirin? |
Ibruprophen |
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Why do people take antacids? |
Stomach has overacidity |
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What are the chances that a person with a .08% blood alcohol level would have a car crash? |
4xs as likely |
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What is normal body temperature? |
37°C |
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What bone should you use to determine sex of skeletal remains? |
Pelvis |
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What bone is best to use to determine age? |
Skull |
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What is the best bone to use to determine race? |
Skull |
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What is the difference between male and female pelvis? |
Male: narrow Female: larger, circular |
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What insects show up first on a dead body? |
Blow fly |
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What are the stages of a blow fly life cycle? |
Egg 3 larvae stages Pupae |
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What will affect the growth of insects? |
Climate, weather, geographical location, drugs/toxics |
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What are the stages and characteristics of each stage of decomposition? |
Fresh, bloat, active decay, advance decay, dry remains |
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Anterior: |
Front
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Posterior:
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Back |
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Medial: |
Towards midline |
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Lateral: |
Away from midline |
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Superior: |
Towards head, relatively higher |
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Inferior: |
Away from head, relatively lower |
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Proximal: |
Closer to any point of reference |
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Distal: |
Farther than any point of reference |
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What is rigor mortis? |
Stiffining of muscles |
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What is livor mortis? |
Lividity |