Biology Basics
While it cannot identify a specific individual, this type of evidence is used to exclude a person as a suspect.
What is blood-type evidence?
This part of a bloodstain indicates the direction in which the blood was traveling.
What is the tapered end (or tail)?
These smeared patterns are created when an object moves through blood that has already partially dried.
What are wipes?
This is the proper way to package dried blood found on a piece of clothing.
What is in a paper bag?
True or False:Sir William Harvey Discovered three blood types: A, B, and O
What is False?
This property of blood causes its molecules to be attracted to each other, often keeping a drop spherical as it falls.
What is cohesion?
This term describes a blood droplet that falls solely due to the force of gravity.
What is a passive drop?
This type of pattern is created when blood is projected from a moving object, such as a pipe or a bat.
What is a cast-off pattern?
True or False: Scientists only began using the physics of blood-spatter analysis after the O.J. Simpson trial.
What is False?
This role, which involves interpreting the physical characteristics of blood evidence, can be filled by either law-enforcement personnel or laboratory staff.
What is a bloodstain analyst?
This lab test is used to confirm that a blood sample is specifically human.
What is the ELISA test? (Enzyme-Linked Immunosorbent Assay)
This measurement determines whether a bloodstain will appear round or elliptical.
What is the angle of impact?
Blood blown out of the nose or mouth creates this specific type of pattern, often containing air bubbles
What is an expired blood pattern?
Liquid blood evidence should be collected in these types of containers at a crime scene.
What are plastic containers?
If a forensic investigator finds a linear pattern of round blood droplets at a crime scene, they can conclude this action was taking place.
What is a person walking while bleeding?
These specific blood cells are not used to produce a DNA profile.
What are red blood cells?
This two-dimensional area shows where a person was standing or sitting when they began bleeding.
What is the area of convergence?
Droplets less than 1 mm in size are characteristic of this type of high-energy impact.
What is high-velocity blood spatter?
These are the two primary downsides to modern, high-tech crime-scene blood analysis.
What are expense and time?
This type of product reacts with hemoglobin to detect blood, even if it has been cleaned up.
What is a luminol-based product?
To determine this three-dimensional location, an analyst must first know the area of convergence and the angles of impact.
What is the area of origin?
This modern technology is used to estimate exactly when blood was deposited at a crime scene.
What is Raman spectroscopy?
This process involves examining size, shape, and distribution to determine if evidence is consistent with accounts of the crime.
What is Blood Pattern Analysis (BPA)?