Forensic Science Unit 4
What are the three types of fingerprints found in the human population? How often does each occur?
Answer: Three types of fingerprints found in the human population are loop where 60 to 65 percent of the population has them, whorl where 30 to 35 percent have them, and arch where about 5 percent have them.
What is a medulla? What do forensic scientists use this for?
Answer: Medulla is a set of cells that runs through a hair. They use it to compare and identify hair.
What is a precipitin test? What is it used for?
Answer: A precipitin test is used to distinguish between animal and human blood.
What makes fingerprints individual? How do scientists match a fingerprint to a specific person?
Answer: The individuality of fingerprints is due to ridge characteristics, which are ridge endings, enclosures and other details. Forensic scientists look for point-by-point comparisons in order to determine whether two fingerprints are the same.
How are fingerprints discovered at crime scenes?
Answer: A device called the Reflected Ultraviolet Imaging System (RUVIS) aims UV light at areas where fingerprints may be.
Of the three types of physical evidence discussed in this unit, which one do you think you would be most interested in working with in an investigation? Why?
Answer: I would be interested in working with the whorl fingerprints because those are the ones I have.
What do you think would be the most challenging aspect of collecting and analyzing hair samples? Why?
Answer: looking for medulla because usually not all hair might have it.
Why do you think forensic scientists study bloodstain patterns? What can be learned from them?
Answer: They need to make sure it is blood or another substance. They can learn who it belonged to especially if it is dried.
Out of the types of evidence discussed in this unit, which one do you think is the most important piece of evidence? Why?
Answer: collecting hair samples because