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Forensic Science Final Exam ReviewHuman Identity (Fingerprints, Forensic Anthropology, DNA)1.Who developed the system known as anthropometry? Bertillion2.Who postulated the exchange of evidence principle? Locard3.In comparing footwear samples, you look for both class and individualizing characteristics. Giveexamples of each. Class: tread pattern, shoe size, logo Ind: gauge/hole in sole, wear pattern4.What are 4 factors that can be rightfully cited as an explanation for the rapid growth of crime labsduring the last 25 years?Increase in crime rateSupreme Court decisions during the 1960’s that resulted in fewer confessionsIncreased drug useAdvent of DNA profiling5. Which unit has the responsibility for the examination of body fluids and organs for the presence ofdrugs and poisons? the toxicology unit6.The final evaluator of forensic evidence is the jury.7.The first rule in crime scene photography is: do not touch/move/disturb evidence unless it is inimminent danger of being lost/destroyed8.What factors help an investigator decide how to search a crime scene?Size of scene, locale, type of crime, available search team, scope of scene9. Any object that can establish that a crime has been committed or can link a crime and its victim orperpetrator is called physical evidence.10.Whose responsibility is it to secure the crime scene? The first responding officer11.Why must notes be taken during the documentation of a crime scene? the investigator may be calledupon months or years later to testify and cannot rely on his or her memory alone to recalldetails of the scene.12.Hair samples, blood samples, bullets, hand swabs, etc, are all evidence that would logically foundor taken at what kinds of crime scenes? Violent crime13.List some techniques scientists use in order to be able to visualize latent fingerprints: oblique lighting,alternate light source, special powders, chemical reagents, superglue fuming14. Which skeletal features are most useful in estimating skeletal age? Skull (teeth, sutures) and otherplaces on the skeleton where growth plates (epiphyses) fuse as the person ages15.The skull and the pelvis are the most sexually dimorphic features of the human skeleton.

16.The analysis of skeletal remains within a legal investigation is called forensic anthropology.17. How do male and female skeletons compare prior to puberty? They are virtually identical Whichfeatures about the human skeleton allow us to determine gender? Skull and pelvis are most helpful,but male skeleton is more “robust” while the female is more “gracile” Age? Sutures, dentition,growth plates Stature length of long bones and analysis with regression formulas18.What is “The Body Farm”? a research facility where human remains are studied as they decay inorder to gain a better understanding of decay processes and timelines19.The cooling of the body after death is referred to as algor mortis.20. Loops, whorls, and arches are considered to be which type of characteristic? (Class, individual, etc)21.Under which circumstances have two people been found to have identical fingerprints? None to date22. What is AFIS? Database for fingerprints What is CODIS? Database for DNA23. From whom, and in what proportions, do you inherit your DNA? Half from each parent24. Why is DNA considered to be the “gold standard” of identification? it is statistically unique and isscientifically analyzed (there is not subjectivity about it)25. Under what circumstances might two people have identical DNA? Identical twins26. How is DNA analyzed (2 lab techniques that we discussed)? Traditional gel electrophoresis andcapillary gel electrophoresis27. How is the identification of a victim, suspect, etc. different in reality from what is portrayed in TV crimeseries? Not everyone is in CODIS or AFIS and the time that it takes to identify someone/solve a crimeis much longer than what is usually portrayed on television28. What does a forensic odontologist study? Teeth What kinds of evidence might s(he) analyze? Dentalrecords, skeletal remains of the jaw and teeth, bite marks29. Are crime labs infallible? No- in fact, some have been found to have corrupt individuals who havetainted the cases on which they worked.Trace Evidence Analysis and Identification30. In general, hairs and fibers are difficult to individualize. Because of this, they are considered to havemainly class characteristics.31. The central region of a hair may contain a structure called the medullainterrupted, or fragmented.32.The follicle tag is the part of the hair that is most likely to contain DNA., which may be continuous,

33.If DNA is found from hair and is matched to a known DNA sample, then the hair is considered to haveindividualizing characteristics.34.One difference between human and animal hair is the frequent absence of the medulla in humans.35.The outer layer of a hair is the cuticle and it is covered in scales made of keratin.36.The natural color of a strand of hair is determined by the number and concentration of pigment granuleswhich are made of forms of melanin.37.Synthetic fibers are made of large molecules called polymers which are made of smaller repeating unitscalled monomers. These fibers are mass produced. Why is that a problem for forensic scientists? Itincreases the number of potential sources of fiber evidence38.Give 4 examples of natural fibers. Cotton, silk, flax, hemp, asbestos What is the most common one?cotton39.The first 2 characteristics that a fiber expert will compare in synthetic fiber sample arecross sectional shape and cross sectional diameter40.One characteristic of a fiber can be that it might have two different indices of refraction. The differencebetween these indices is called birefringence41. List (in order) the three stages of hair growth. Anagen, catagen, telogen42.This hair growth stage is characterized by rapid cellular division in the root: anagen43. Paint evidence is often analyzed by crime labs. What value can it have? Often transferred to tools orautomobiles during crimes- can be used to associate two objectsWhat tools do experts use to analyze and compare paint samples? Microscopes, pyrolysis gaschromatography44. Soil (and other related material) is best examined by a forensic geologist45. Soil can be useful evidence because: it can be carried into and out of crime scenes and can be“narrowed down” to particular source areas. Also, it may contain contaminants or peculiarmaterials specific to a certain location. Soil in a tire well can indicate where, and in whichorder, a car has travelled.46. What role did trace evidence play in the McDonald murder case? There were synthetic fibers thatwere in question in an appeal and they were found to be consistent with the victim’s wig.47. What famous case involved the analysis of trace metals? The Kennedy AssassinationTools of the Forensic Scientist48.What is one effect of the fact that light is a form of electromagnetic radiation? It can move through avacuum (like space)- does not require a medium (material) in order to travel.

49. What is the mathematical relationship between the frequency, wavelength, and speed of light? c λf50. As wavelength increases, which color end of the visible spectrum is approached (blue or red)?51. What is refraction? When the path of light is bent as the light moves from one material to another52.In two of your labs, you used a device called a colorimeter. This instrument could be set at differentwavelengths and was able to measure the absorbance of light by a solution. (our colorimeteruses the visible spectrum)53. The general relationship between absorbance and concentration is known as Beer’s law, and is whatkind of mathematical relationship? Direct (as concentration increases, absorbance also increases)54. How would the relationship in #53 look in a graph? Linear55. How could we use the colorimeter in a forensics lab? (What applications could it have?) toxicology(determining concentration of poison/drug in a sample) analysis of pigment-containingsubstances (like ink from a ransom note or bad check)56. What is the name for the little containers that we used in the colorimeter? cuvettes57. What does each of the following do: gas chromatograph, mass spectrometer, FTIR, thin layerchromatography? For each test, indicate whether the results are definitive or presumptive.GC: separates mixtures into constituent parts using a carrier gas; high speed and reliable, butpresumptive resultsMS: analyzes substance (or parts of a substance) based on the behavior of ionized particles asthey move through a magnetic field; the results are definitiveFTIR: analyzes substances based on their infrared “fingerprint”; definitive resultsTLC: inexpensive, easy, fast- separates mixtures into component parts; Rf values can becompared to known substances; presumptive results58. How is gas chromatography used in tandem with mass spectrometry? The parts that are separated viaGC are sent directly to MS59. What is an analyte in a chemical testing situation? The material being analyzed60. Differentiate between the electron microscopes, comparison microscope, stereomicroscope, compoundlight microscope, and micro-spectrophotometer. (What is each “good for?”)Electron microscopes (TEM, SEM): extremely high magnification potentials, high resolution; useelectrons instead of visible lightComparison Microscope: side by side light microscopes connected by optical bridge; allows userto see magnified images side by sideStereomicroscope: upright, 3D image. Low magnifications but great for “scanning” large, bulkyitems for trace evidence.Compound light microscope: best “general tool” with variable magnification levelsMicro-spectrophotometer: instrument that is attached to a compound light microscope andallows chemical analysis of materials as on observes them on a sample