Forensic Science Final Exam Review

Forensic Science – Final Exam Review

Chapter 1  Define the following terms: Forensic science, expert witness, Locard’s exchange principle, toxicology, anthropometry  Recognize the major contributions to the development of Forensic Science.  List four methods that have been used by forensic scientists to identify individuals and place them in chronological order according to their development.  Account for the rapid growth of forensic laboratories in the past forty years.  Describe the services of a typical crime laboratory.  Describe the major crime labs operated by the U.S. Federal government.  What were the important principles established in the court cases Frye v. United States and Daubert v. Merrell Dow Pharmaceuticals, Inc. as related to the admissibility of scientific evidence in federal courts?  What is the main difference between the testimony given by an expert witness and that given by a lay witness?  List and describe the responsibilities of a forensic scientist.

Chapter 2 1. Define the following terms: physical evidence, chain of custody, standard/reference sample, buccal swab, substrate control, rigor mortis, livor mortis, algor mortis, autopsy, forensic anthropology, forensic pathology, forensic entomology 2. Describe the important role physical evidence plays as compared to eyewitness testimony, and confessions in criminal court cases. 3. Describe the responsibilities of the first police officer who arrives at a crime scene 4. Explain the steps to be taken to thoroughly record the crime scene. 5. Understand the various systematic methods for searching a crime scene. 6. Describe the proper techniques for packaging common types of physical evidence. 7. Explain the roles of the forensic pathologist, forensic anthropologist, and forensic entomologist in a homicide investigation Questions: 1. Why is it important to exclude onlookers from a crime scene? 2. What is the most important requirement for photographing a crime scene? 3. In what situations is an autopsy typically performed? 4. What are some methods that a forensic scientist can use to approximate time of death?

Chapter 3  Define the following terms: identification, comparison, individual characteristics, class characteristics, crime scene reconstruction  Review the common types of physical evidence encountered at crime scenes.  List and explain the function of national databases available to forensic scientists.  Explain the difference between the identification and comparison of physical evidence.  Define and contrast individual and class characteristics of physical evidence.

Chapter 4 Forensic Science – Final Exam Review

 Define the following terms: density, refractive index, concentric fracture, radial fracture, refraction, Becke line  Describe the manner in which density and refractive index are measured for samples of physical evidence.  Define and understand the physical properties of glass used by forensic scientists.  Describe the composition and uses for various types of glass. Describe the types of information that can be obtained by analyzing broken glass evidence.  Explain how the 3R rule is used by forensic scientists in the analysis of glass.  Explain the jigsaw effect and how it relates to the analysis of glass evidence.  How might a forensic scientist tell which of two fractures on a piece of glass was created earlier? Questions: 1. What is the only way to individualize glass fragments found at a crime scene to a single source?

Chapter 5  Define the following terms: precursor, analog, spectrophotometry, chromatography  Understand how the Controlled Substances Act regulates drugs, precursors and analogs.  Describe the difference between screening and confirmation tests. List several methods for each.  Understand the advantages and limitations of color tests and microcrystalline tests for detecting the presence of drugs.  Name three distinct advantages of gas chromatography in the identification of drugs. What is the main drawback of gas chromatography in the identification of drugs?  Describe how infrared and ultra-violet spectrophotometry are used to analyze drugs.  What analytical device is a gas chromatograph often connected to in order to analyze drug mixtures? Why? Questions: 1. What is the most widely used illicit drug in the United States? Under what class of drugs is it listed and what are its short-term physical and psychological effects at low to moderate doses? 2. What is the most widely abused drug in the United States? Under what class of drugs is it listed and what are its short-term physical and psychological effects at low to moderate doses? 3. On what three criteria does the Controlled Substances Act classify dangerous substances? 4. What is the difference between a qualitative evaluation and a quantitative evaluation of drug evidence?

Chapter 6  Define the following terms: toxicologist/toxicology, metabolism, implied-consent law Forensic Science – Final Exam Review

 Explain how alcohol is absorbed into the bloodstream, transported throughout the body, and eliminated by oxidation and excretion.  Name at least three factors that influence the rate at which alcohol is absorbed into the bloodstream.  Describe techniques that forensic toxicologists use to isolate and identify drugs and poisons. Questions: 1. What is a toxicologist? Name three settings in which a toxicologist often works. 2. What scientific observation forms the theoretical basis for breath testing? 3. What type of container best ensures the preservation of blood samples and why? What two substances should be added to a blood sample after collection and why? 4. Describe challenges toxicologists face in detecting drugs and determining their toxicity.

Chapter 8  Define the following terms: luminol,  List the various techniques for analyzing or characterizing bloodstains.  Explain how surface texture affects the appearance of blood spatter  Explain how the direction of travel can be determined from a blood droplet  Explain how the angle of impact of a blood droplet can be determined from a bloodstain  Explain how the origin of blood spatter can be determined Questions: 1. What technique replaced blood typing for associating bloodstain evidence with a particular individual? 2. What 3 questions must the criminalist answer when examining dried blood?

Chapter 9:  Define the following terms: DNA, nucleotide, complementary base pairing, proteins, amino acids, replication, polymerase chain reaction (PCR), tandem repeat, restriction fragment length polymorphisms (RFLP), electrophoresis, short tandem repeats (STR)  Describe the procedures for proper preservation of biological evidence for laboratory DNA analysis  Explain the reasons that scientists or criminologists would investigate DNA finger prints.  List and describe the components of a nucleotide. How are nucleotides linked to form the double helix known as DNA?  Describe the process of DNA replication. What is the importance of DNA replication?  List two advantages STRs have over restriction fragment length polymorphisms (RFLP).  What is CODIS? How is CODIS useful to forensic scientists?  How are reference samples obtained from possible suspects?

Chapter 10 Define the following terms: cuticle, cortex, medulla, follicular tag, natural fibers, manufactured fibers, polymer, monomer  distinguish between animal and human hair  list hair features that are useful for microscopic comparison Forensic Science – Final Exam Review

 explain proper collection of forensic hair evidence  describe and understand the role of DNA typing in hair comparisons  understand the differences between natural and manufactured fibers.  list the properties of fibers that are most useful for forensic comparisons  describe the proper collection of fiber evidence.

Chapter 14  Define the following terms: anthropometry, arch, loop, whorl, latent fingerprint, visible print, plastic print, ridge characteristics  Describe the 3 fundamental principles of fingerprints that are useful to forensic scientists.  List the three major characteristics of fingerprints used for classification  Distinguish visible, plastic, and latent finger prints  List the techniques for developing latent fingerprints  Describe the concept of an automated fingerprint identification system Questions: 1. When using AFIS, who makes the final verification of a print’s identity? 2. What are some drawbacks or limitations in using AFIS? 3. How are prints from hard and non-absorbent surfaces developed? 4. How are prints from soft and porous surfaces developed?