Finding skin cells on a doorknob at a crime scene is an example of what theory?
A.
Theory of General Relativity
B.
Principles of DNA
C.
Principles of Trace Evidence
D.
Theory of Vector Analysis
C. Principles of Trace Evidence
What is the most basic unit that makes up a piece of granite?
A.
grains of dirt
B.
cells
C.
sand
D.
atoms
D. atoms
The correct answer is C. Principles of Trace Evidence.
When investigating a crime scene, forensic analysts use various techniques to collect and analyze evidence. Trace evidence refers to small, often microscopic, pieces of material that can be transferred between individuals or objects during a criminal act. Skin cells are a type of trace evidence.
To find skin cells on a doorknob, investigators would likely use a technique called swabbing. They would swab the doorknob, carefully collecting any trace evidence, including skin cells that may be present. Once collected, the swabs would be sent to a laboratory for analysis.
In the lab, forensic scientists would typically use a technique called DNA profiling or DNA analysis to determine the origin of the skin cells. DNA analysis involves isolating and analyzing specific regions of DNA in order to create a profile unique to each individual. By comparing the DNA profile from the skin cells found on the doorknob to potential suspects or the DNA profiles stored in a database, investigators can narrow down the list of possible sources.
Therefore, finding skin cells on a doorknob at a crime scene is an example of the principles of trace evidence, as it involves the collection and analysis of small pieces of material that can provide crucial information in a criminal investigation.