Review Questions for All Chapters
Introduction to Forensics (Chaps 1, 10)
What is forensic science and what disciplines comprise forensic science?
In class, we talked about 5 pieces of information that can be determined at a crime scene.
What are these five things?
What organization has standardized the way forensic investigations proceed?
This organization also defined 9 principle areas of forensic science. Know, in general, what these areas encompass:
toxicology
serology
pathology
anthropology
odontology
questioned documents
psychiatry
geology
engineering
What four scientific advances have revolutionized forensic science? How has each influenced criminal investigation?
Forensic techniques rely on scientific discoveries. What rules has the federal government established for the introduction of new scientific methods into courtroom proceedings?
Introduction to Chemistry and Latent Fingerprinting Techniques (Chap 17)
Know the relationships between elements and compounds. How are the atoms that make up a compound held together?
What differentiates an inorganic molecule from an organic one?
What is meant by the electronegativity of an element? How does electronegativity contribute to the polarity of a molecule? What is a polar molecule?
Skin is made up of two layers – the epidermis and the dermis. What do each of these layers accomplish for the body?
Where do fingerprints originate – dermis or epidermis?
There are three glands that secrete material responsible for the material we consider to be fingerprints.
What are these three glands? What compounds or substances do each primarily secrete?
What two factors most contribute to the amount of material deposited with a fingerprint?
Besides water, fingerprints contain four main components. What are these components?
Know the general usefulness, pros, and cons of each of the fingerprinting techniques we covered in class. Know which secretions from above are useful in each of the fingerprinting techniques.
It is not necessary to know chemical structures of the compounds we studied.
Arson and Explosives (Chapters 24)
What is an accelerant? What type compounds are accelerants usually categorized as (inorganic or organic)?
What is combustion? When an organic molecule reacts with oxygen, what two products should be formed? Why do ash, smoke, and other gases (carbon monoxide) also form?
Where does the energy we associate with a combustion reaction come from? In what forms do we observe this energy?
What type clues may lead investigators to believe a fire may be arson?
What are the four main steps to investigating suspected arson or bombing cases?
What are the four methods we discussed for isolating and concentrating accelerants? In general, how does each one work?
What does GCMS stand for? In general, how does a GC work? What chemical property
determines how fast a molecule will travel through a GC column?
A GC has many parts: carrier gas, column, and detector. What role does each part play in analyzing an unknown sample?
GCs are usually coupled to s mass spec. How does an MS work? What are we actually determining by reading the results from an MS?
What is the definition of forensic toxicology? What is the difference between a poison and a toxin?
What are the four types of death investigated by toxicologists? What are common examples of these types?
What must be proven for successful prosecution of a poisoning case?
Why does a forensic toxicologist takes samples of all body fluids and tissues for analysis?
What is meant by biotransformation? Define the word metabolite.
What reasons are there for beginning toxicology work as soon as possible after the death of an individual?
What are the general classes of poison? What class of poison do many chemical substances fall under? Know what is meant by acid, base, neutral, amphoteric, and alkaloid.
We discussed six different detection methods for finding and identifying drugs/poisons in biological samples:
a. color test
b. microdiffusion test
c. TLC, GC, and HPLC (What do these stand for?)
d. Spectroscopy (What forms of electromagnetic radiation are most useful in forensic study?)
e. Mass Spectrometry
f. Immunoassay
How do these techniques, in general, work?What are advantages and disadvantages of each (only what we discussed
in class)?
What is forensic serology? What is the origin of the word “serology”?
Including liquid and solid material, what are the major components of blood?
What are the roles of red and white blood cells? Which is more useful to a forensic investigator?
There are three questions for which forensic serologists seek answers. Is a substance blood? Is it human blood? Who’s blood is it? What are the three common methods used to determine if a substance is blood? What are possible advantages and disadvantages of each?
What part of blood is specifically looked for by the luminol test? What other chemicals are involved in luminol detection?
What is the precipitin test? What are the general steps involved? Can the precipitin test be used to determine what species a blood sample came from if it is not human blood?
What is the difference between a blood antigen and blood antibodies? What are the two antigen systems used most often in blood testing? What are the general steps used to determine an individual’s blood type? Why is this not the best method for identifying a specific individual?
Why is O negative blood the universal donor? Why is AB the universal acceptor?
Semen is commonly found at specific types of crimes. What enzyme is present in semen that allows a simple test for it’s presence? What are the advantages and possible disadvantages of this method?
What is DNA?
What does it stand for and what role does it play in a living system?
Where in the cell is it found?
What is meant by the terms "chromosome" and "gene"? How do they differ?
What are the three parts of a nucleotide?
What are the four possible nitrogenous bases that are found in DNA?
DNA is double-stranded (composed of two strands of nucleotides). What force holds these strands together?
Why is A (adenine) always paired with T (thymine) (and C with G)?
What enzyme is responsible for DNA replication?
What are the general steps involved in DNA replication?
In general, what is a restriction enzyme?
What purpose do they serve in nature and how are they used in forensics?
Gel electrophoresis separates DNA fragments based on size. What two common types of gels do forensic investigators use?
Why does DNA migrate in an electric current?
What causes DNA fragments to migrate faster or slower than other fragments?
What does VNTR stand for?
Why are these regions of a chromosome useful to a forensic investigator?
What does PCR stand for?
Why is it used in forensic science?
In general, how does it amplify DNA?
Why is the discovery of Taq polymerase so useful to PCR?
What are the general steps of DNA fingerprinting? What is the purpose to each step (why do we do it?)?
Define pathology. What is the root of this word?
What 3 broad roles did we assign to a forensic pathologist?
What is the difference between the “cause” of death and the “mechanism” of death?
How, in general, does a pathologist determine the time of death?
We looked at six unpleasant post-mortem changes that may hinder of aid a forensic pathologist. What are these changes and what are the signs or symptoms of each?
We looked at six types of wounds that may aid a pathologist in determining a cause of death or reconstructing a crime scene. What are these categories and what are the characteristics of each?
How do each of the following aid a pathologist? (What information can we gain about the crime from each?):
a. length and depth of a wound
b. location of a wound on the body including where the wound starts and where it ends
c. where a wound occurs on a body
What are the general procedures followed during an autopsy? Why are the organs weighed andexamined? Why are tissue samples and samples of all fluids or foreign materials kept?
Why is the brain stored in formaldehyde for 10-14 days before examining?
What aspects of criminal investigation are focused on in forensic anthropology and forensic odontology?
What are the 5 roles of a forensic anthropologist?
What are the common ways an anthropologist may try and determine the time of an individual’s death?
For demographic purposes, what bones are best for determination of a person’s age? Sex? Race? Stature?
What are the general steps of facial reconstruction? What are the most important indicators an anthropologist would use in the facial reconstruction process (i.e., sex, race, etc)?
Although not always successful, what clues can lead a forensic anthropologist to help determine the cause of an individual’s death?
Other than the shape of the teeth, what other aspects of dental records allow ease in human identification?
For the periods of pregnancy-15, 15-22, and 23+, how are dental records used to determine a person’s age? What teeth are best?