Criminal Inv-Chapter 5, Laboratory and Technical Serv Flashcards Preview

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Flashcards in Criminal Inv-Chapter 5, Laboratory and Technical Serv Deck (44):
1

trustworthiness of an expert is important to the net worth of the ___ _____

entire investigation

2

Any suspicion of subjectivity or dishonesty destroys the legal significant of evidence

becuase the average trier of facts may easlily view such conduct as affecting the credibility of the entire investigation

3

criminalistics

is the profession and scientific discipline directed to the recognition, identification, individualization and evaluation of physical evidence by application of the naturla sciences in matters of law and science

4

identification in criminalistics is aligned with the logic of __

set theory- all objects can be divided and subdivided into various sets on the basis of their properties. identification in relation to physical evidence and its analysis is defined as the determination of some set to which an object or substance belongs

5

primary carrier of genetic information in living organisms, consists of a long, spiral structure that has been likened to a twisted ladder

molecule of DNA

6

handrails of the ladder string together to form the ladder rungs. Each rung consists of a

base pair- two of four varieties of nucleic acid and are combined in pairs called nucleotides

7

the sequence of these base pairs constitutes the genetic coding of

DNA

8

DNA in humans is found in all cells that contain a nucleus- except

red blood cell

9

Each nucleated cell usually contain a full complement of an individuals DNA called __

genome

10

Genome consists of approx how many base pairs? of which about ____actually differ from person to person

3 billion base pairs
3 million

11

person-to-person differences within a particular segment of DNA sequence ar referred to as

alleles

12

polymerase chain reaction -PCR

extracting DNA from small evidence sample and then replicating it thru a complex operation of repeated heating and cooling cycles and exposure to an enzyme. Each cyle doubles the quantity of DNA. by examining several locations (loci) where variations occurs, a typing profile can be produced

13

Short tandem repeats-STR

FBI has selected thirteen STR loci to serve as a standard battery of core loci,

14

According to standard PCR protocol. Each dark spot that appears can be read as "yes" or
"no" to the question of whether a particular individual possesses a given

allele

15

a difference of a single allele can exclude someone as the donor of that evidence sample. the more locations that show the same allele pattern, the stronger the evidence that the two samples came from the same individual

allele

16

DNA is found in

all body tissues and fluids, saliva, skin cells, bone, teeth, tissue, urine, feces and host of other biological specimens.

17

DNA molecule is long lived, it is likely to be detectable for many years in bones and body fluids stains from older criminal cases

DNA

18

human cell contains two tpes of DNA.

nuclear and mitochondrial

19

nuclear DNA

contains 23 pairs of chromosomes in the nuclei of the cells and each parent contributes to the genetic makeup of the chromosomes

20

Mitochondrial DNA-mtDNA

is found outside the nucleus and is inherited soley from the mother. there are hundred of thousands of mitochondria copies in human cell compared to just one nuclear DNA located in the same cell

21

Scientist use mtDNA to identify subject when

nuclear DNA is significantly degraded, such as charred remains.

22

mtDNA is more vigorous, time consuming and costly than nuclear DNA profiling

only a handful of forensic labs process evidence for mtDNA determinations

23

spectrography

the radiation from incandescent gas or vapor is concentrated in certain discrete wavelengths. It will produce a complete elementary analysis of evidence sample containing mineral and other inorganic compounds. it is an all-purpose intrument for criminalistics

24

chromatography

method of separating compounds to identify the components. such as illegal drugs or poison

25

Gas chromatographs

analytical tool becuase with them microsamples of such complex compositions as gasoline, fuel oil, perfumes, hair dressings and paint thinners can be identified from their constituents

26

X-ray crystallography

identifing of any crystalline solid or compound from which a crystalline sold derivative can be made

27

X-ray diffraction

used in proccesing very small samples in examining samples with noncrystalline impurities and identifying inorganic and mineral substances

28

X-ray spectra

used for analysis and identification

29

neutron activation analysis-NAA

can analyze samples one hunderd times to small for ordinary spectrographic techniques.

30

gamma-ray-spectrometer

to measure the distinctive radioactive gamma-ray emissions and thereby to identify elements from which the rays originate.

31

NAA technique and its application in the study of gunshot residues have returned a potential item of evidence to investigators.

empty

32

paraffin-lifing kits are used on suspects hands and NAA measurments for the presence of

antimony and barium, which are common gunshot residues,

33

trace metal detection technique-TMDT

distinctive signatures of handguns, tools and other metal objects .

34

ultrasonic cavitation

etching method used for restoring obliterated serial numbers on firearms and other metal objects

35

lasers

used in detection of latent fingerprints and of questioned documents.

36

voiceprinting

identification of voices.

37

crytography

use of simple ciphers and codes to protect the security of messages

38

substitution cipher

most common cipher used.

39

transposition ciphers

change in the order of the enciphered material

40

reversal transposition

reversed numbers

41

split combination

empty

42

National Integrated Ballistic Information Network-NIBIN

maintained by ATF. database on fired cartridge casings, bullets, shotgun shells.

43

International Forensic Automotive Paint Data Query-PDQ

developed and maintained by Forensic Laboratory Services of the Royal Canadian Mounted Police. Database contains chemical and color info pertaining to factory auto paint and can determine make,model,year and assembly plant on more than 13000 vehicles. Contributors to database include Canada, US as well as 21 other countries.

44

Shoeprint Image Capture and Retrieval-SICAR

shoe sole database