Forensics Final Exam -5 essays PDF

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5 short essays showing key ideas of what we learned in the course...

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1 FORENSICS FINAL EXAM Essay #1 In a homicide case I would expect to find a body, blood and other identifying evidence, possibly a murder weapon, and hopefully fingerprints. After closely photographing and visually analyzing and documenting the scene I would then collect and package evidence as well as different samples from the victim and the crime scene in order to associate the victim, suspect, and crime scene with each other. I would first collect any blood whether it be on the victim, weapon, or somewhere around the crime scene, this will not only identify the victim, but tie the victim to the crime scene, in some cases the suspect’s blood may even be found, also tying them to the crime scene. I would next collect the murder weapon which should also carefully be analyzed for any fingerprints, if none are found the murder weapon will still be a key in either tying the weapon to the suspect or confirming that it is indeed the cause of the victim’s death. Then, I would collect any hair, bone, skin, nails (scrape under victim’s nails), or teeth since they can also be used for DNA identification. Lastly, I would submit any other evidence that would be important in the case (items containing a fingerprint, any digital evidence, etc.)

Essay #2 The difference between class characteristics and individual characteristics is that class characteristics are characteristics that can be applied to a specific group of people that may share a certain trait. Individual characteristics are characteristics that are specific to one single person and is not shared with anyone else in the world. Regarding fingerprints, class characteristics are the type of print (whorl, loop, arch) and an individual characteristic would be the number of ridges, cores, bifurcations, etc. that an individual’s fingerprint possesses that classifies one individual’s loop print from another. Regarding bullets and cartridge casings, a class

2 FORENSICS FINAL EXAM characteristic would be the type of bullet identified or the specific type of cartridge case. Individual characteristics are the unique activity marks or scratches that occur after a gun is fired that can be located on the bullet or within the cartridge case. As far as footwear impressions are concerned, class characteristics are the type of shoe, brand, where it’s sold. The individual characteristics are harder to find; maybe there’s unique damage done to the sole of the shoe or it’s more worn in on the inner sole than the outer side (worn by someone that’s flat footed.)

Essay #3 The difference between nuclear and mitochondrial DNA is that nuclear DNA is the standard DNA you find in the nucleus of a cell with 46 genes, 23 inherited from mom, 23 inherited from dad, whereas mitochondrial DNA is inherited from a single lineage of ancestors. “Forensic scientists are offered enhanced sensitivity and the opportunity to characterize mtDNA when nuclear DNA is significantly degraded, such as in charred remains, or when nuclear DNA may be present in a small quantity (such as in a hair shaft).” (Saferstein, 2018.) When an mtDNA sample is not possible, investigators can obtain a reference sample from any maternal relative. MtDNA is also very time consuming and more costly than nuclear DNA profiling. Nuclear and mitochondrial DNA can both be found in the same types of biological evidence. Some types of biological evidence that can be analyzed and are commonly collected include; sweat, semen, blood, hair, teeth, saliva, urine, tissue, rectal and vaginal cells, and skin.

Essay #4 Drugs are classified into 4 different categories; narcotics, hallucinogens, depressants, and stimulants. Narcotics are defined as “an analgesic or painkilling substance that depresses vital

3 FORENSICS FINAL EXAM body functions such as blood pressure, pulse rate, and breathing rate; regular administration of narcotics produces physical dependence.” (Saferstein, 2018.) Heroin is a commonly abused narcotic, it can be smoked and snorted but is most commonly injected, it stimulates the part of the brain that produces dopamine and thus creates a a reinforcement of drug taking behavior. A hallucinogen is “A substance that induces changes in mood, attitude, thought processes, and perceptions.” (Saferstein, 2018.) A commonly used hallucinogen is LSD, it’s extremely potent and produces vivid hallucinations, frequent and sudden mood changes, and sometimes even anxiety and tension. Depressants can be defined as “A substance that depresses the functions of the central nervous system; depressants calm irritability and anxiety and may induce sleep.” (Saferstein, 2018.) A barbiturate is a type of depressant, it acts as a “downer”, it gives the body a feeling of relaxation and produces sleep. They suppress the vital functions of the central nervous system. A stimulant is “A substance taken to increase alertness or activity.” A popular stimulant is cocaine, a highly addictive drug that creates a sense of happiness and euphoria for the user. It acts as a stimulant to the central nervous system and suppresses hunger and fatigue while amplifying alertness and vigor.

Essay #5 After watching an episode of CSI, there were a couple of things that stood out to me that were very obviously different than how forensic scientists work in the real world. The main thing I noticed was how fast the case progressed, the tv-show homicide seemed to be investigated and solved within a couple of days which is extremely unrealistic and not the way that real-life homicide cases work. Realistically speaking, a crime scene alone can take days to investigate and collect evidence from. After the evidence is brought to the lab it can sometimes take several

4 FORENSICS FINAL EXAM weeks to yield any test results or find any matches/prime suspects. Another discrepancy I noticed in the tv-show is how they falsified some forensic technology, even though modern technology is extremely advanced, it’s not so advanced that you can scan a fingerprint and automatically yield a perfect match and thus have found the killer. In forensics there are a lot of dead ends you encounter and technology is not so advanced as to solve the entire crime within days.

5 FORENSICS FINAL EXAM References Saferstein, R. (2018). Introduction. In Criminalistics: An Introduction to Forensic Science(12th ed.)....