CSI Forensic Analysis Techniques 1 — Questions and Answers
Question 1: What is the purpose of DNA analysis in forensic investigations?
- To identify individuals through genetic material (Correct answer)
- To determine the cause of death
- To analyze handwriting samples
- To reconstruct crime scenes
Correct answer: To identify individuals through genetic material
DNA analysis is a powerful forensic tool used to create a unique genetic profile from biological samples like blood, saliva, hair, or skin cells. This profile can then be compared to known individuals or databases to identify suspects, victims, or establish connections between individuals and a crime scene. It provides highly reliable identification for investigations.
Question 2: Which forensic technique is used to analyze gunshot residue (GSR)?
- Scanning Electron Microscopy (SEM) (Correct answer)
- Polygraph testing
- Fingerprint lifting
- Blood spatter analysis
Correct answer: Scanning Electron Microscopy (SEM)
Scanning Electron Microscopy (SEM) is the primary technique used to analyze gunshot residue (GSR) particles. SEM can detect the characteristic morphology and elemental composition (lead, barium, antimony) of GSR particles, which are unique to firearms discharge. This allows forensic scientists to determine if a person has recently fired a weapon or was in its vicinity.
Question 3: What is the primary purpose of toxicology testing in forensic science?
- To detect substances in biological samples (Correct answer)
- To match a suspect’s handwriting
- To determine blood type
- To examine tool marks
Correct answer: To detect substances in biological samples
Toxicology testing in forensic science focuses on identifying and quantifying drugs, poisons, and other chemical substances in biological samples such as blood, urine, or tissue. Its primary purpose is to determine if these substances played a role in a death, impairment, or criminal act. This analysis helps establish cause and manner of death or influence on behavior.
Question 4: Which method is commonly used to identify latent fingerprints?
- Dusting powder or cyanoacrylate fuming (Correct answer)
- Blood spatter analysis
- DNA sequencing
- Forensic odontology
Correct answer: Dusting powder or cyanoacrylate fuming
Latent fingerprints are invisible to the naked eye and require specialized techniques to visualize them. Dusting powder adheres to the oils and sweat, making the print visible, while cyanoacrylate (superglue) fuming chemically reacts with print residues to create a white, stable print. Both are common and effective methods for developing and identifying latent prints.
Question 5: What is forensic ballistics used for?
- To analyze firearm-related evidence (Correct answer)
- To detect forged documents
- To determine a person's DNA profile
- To identify human remains
Correct answer: To analyze firearm-related evidence
Forensic ballistics is the scientific examination of evidence related to firearms and ammunition. This includes analyzing bullets, cartridge cases, and firearms to determine if a specific weapon was used in a crime, the trajectory of a bullet, and the type of firearm involved. It provides crucial links between weapons, victims, and suspects in criminal investigations.
Question 6: How does forensic entomology assist in criminal investigations?
- To estimate time of death using insect activity (Correct answer)
- To analyze gunshot wounds
- To examine bloodstain patterns
- To perform toxicology screening
Correct answer: To estimate time of death using insect activity
Forensic entomology is the study of insects found at a crime scene, particularly on decomposing remains. By analyzing the species of insects present, their developmental stages, and succession patterns, forensic entomologists can provide a highly accurate estimate of the Post Mortem Interval (PMI), or time of death. This is invaluable in investigations where other methods are limited.
What is the purpose of DNA analysis in forensic investigations?