Principles of Biomedical Science

Mixture of 1.1.1-1.1.5

Plasma

Holds blood cells, white + red + platelets

Transfer Stain

when a bloody surface comes into contact with a secondary clean surface & leaves recognizable smears such as shoe prints & fingerprints.

Passive/Falling Drop

bloodstain created by force of gravity pulling a droplet downward

Radial Splatter

when external force overcomes gravity and strikes a source of liquid blood & sprays droplets in a radiating fan-like pattern from point of impact.

Forensic Scientist

scientist who examines & analyzes evidence from a crime scene.

Biomedical Scientist

scientist who studies the human body and uses that knowledge to analyze medical samples and then helps diagnose.

Link Method

Best used in large or small indoor or outdoor scenes, connects & evaluates relationships between pieces of evidences.

Line Method

Best used in large, open outdoor areas, searchers walk in straight lines in one direction.

Grid Method

Best used in large outdoor areas requiring more than one search.

Spiral Method

Best for scenes without any physical barriers

Wheel

Best used for small, circular areas, searchers start at a center and then walk straight outward in radiating lines.

Zone Method

Best for indoor scenes with complex structures, divides scene into quadrants.

Cortex

Inner most layer of hair, techs examines texture. (pigment)

Medulla

Middle layer of hair, techs examine width and fragmentation.

Cuticle

Outermost layer of hair, techs examine thickness.

Forensic Technician

Specialized professional who seeks, documents, collects, and preserves physical evidence from crime scenes for scientific analysis.

Latent Fingerprint

Print on the surface by oils.

Arch

Ridges slope up and down like a narrow mountain.

Tented Arch

Ridges in the center that thrust upward like a tent.

Loop

Ridges curve back on themselves forming a loop.

Whorl

Ridges form a circular/spiral pattern.

Locard’s Exchange Principle

every time a person makes contact with any other thing there is an exchange of physical material that occurs.

Physiological Response

Physical response to stimuli that can be measured, can be increase in heart rate, skin conductivity, & heart rate.

Vital Signs

Heart Rate, Blood Pressure, Respiratory Rate, Body Temperature, Skin Conductivity.

Polygraph Test

Lie detector test, forensic tool that monitors and records an individual’s vital signs & physiological changes when answering series of questions.

Control Questions

Asked to establish a physiological baseline of how one responds.

Compound Questions

A question joined together using “and” or “or” and only allow for a yes/no answer when in reality could be either denying/agreeing to one or the other.

Chargaff’s Rule

In the DNA of any organism, there is a 1:1 ratio of purine bases to pyrimidine bases. Adenine to thymine & and cytosine to guanine.

Genome

complete set of genetic material (DNA) present in an organism or cell. It contains all the hereditary information needed to build, maintain, and operate that specific organism.

PCR (Polymerase Chain Reaction)

laboratory technique used to amplify (make millions of exact copies of) a specific segment of DNA from a tiny or degraded sample.

Restriction Enzyme

enzyme produced chiefly by certain bacteria that acts as molecular scissors to cut DNA molecules at specific nucleotide sequences. Forensic scientists use them to chop long DNA strands into manageable, variable fragments.

Recognition Site

specific, short sequence of DNA nucleotides (usually 4 to 8 base pairs long) where a restriction enzyme binds and cuts.

Gel Electrophoresis

laboratroy method used to separate mixtures of DNA fragments based on size & charge, with a current, the fragments travel through a gel and show distinct patterns of DNA bands