HOSA Forensic Science — ROUND 1 DETAILED SUMMARY GUIDE

These flashcards cover key concepts from forensic science related to crime scene processing, toxicology, anthropology, and more, serving as a comprehensive study aid.

What principle states that every contact leaves a trace?

Locard's Exchange Principle

Who developed DNA profiling?

Alec Jeffreys

Who is associated with the study of fingerprints?

Francis Galton and Edward Henry

What does Goddard specialize in within forensic science?

Firearms analysis

Who is known for document examination in forensic science?

Albert Osborn

What are the initial steps in crime scene processing?

Secure, separate, scan, photograph, sketch, search, collect

What are the two types of evidence?

Class evidence and individual evidence

Why is chain of custody important?

It ensures the integrity of evidence throughout the investigation.

What is the difference between manner of death and cause of death?

Manner refers to the circumstances (natural, accidental, homicide), cause refers to the specific reason (heart attack, gunshot).

What is the mechanism of death?

The physiological process that leads to death.

What are the postmortem signs?

Livor mortis, rigor mortis, algor mortis, and decomposition.

What is livor mortis?

Postmortem hypostasis, pooling of blood due to gravity.

What is rigor mortis?

Stiffening of the muscles after death.

What is algor mortis?

Cooling of the body after death.

What is decomposition?

The breakdown of bodily tissues after death.

What are the categories of drugs in toxicology?

Stimulants, depressants, narcotics, hallucinogens.

What samples are commonly tested in toxicology?

Blood, urine, and vitreous humor.

What is LD50?

The lethal dose at which 50% of a population would die.

What is the significance of drug tolerance?

The need for increased drug dosage to achieve the same effect.

What is drug withdrawal?

The symptoms that occur when a person reduces or stops taking a drug.

What peculiar symptom is associated with carbon monoxide poisoning?

Cherry red skin.

What is the best indicator of biological sex in anthropology?

The pelvis.

What skeletal features indicate age in anthropology?

Growth plates and cranial sutures.

How is stature estimated in anthropology?

By measuring long bones.

What characteristics are assessed for ancestry determination?

Skull traits.

What are the types of trauma that can be identified?

Blunt force, sharp force, gunshot, and thermal injuries.

What factors influence the blowfly life cycle in entomology?

Temperature and environmental conditions.

How is PMI estimated using entomology?

By assessing the larval stage of blowflies.

What are the main types of bloodstains identified in forensic science?

Low, medium, high velocity stains, cast-off patterns, and direction.

What are presumptive blood tests used for?

To indicate the possible presence of blood.

What are the primary methods for DNA analysis?

Short Tandem Repeats (STR), Polymerase Chain Reaction (PCR), and mitochondrial DNA (mtDNA).

What is important for proper collection of DNA evidence?

Samples must be dried and packaged separately.

What does evaluating competency in psychology mean?

Assessing a person's ability to stand trial or understand legal proceedings.

What does insanity in psychology refer to?

A legal term indicating a person cannot understand their actions due to mental illness.

What are the basics of criminal profiling?

Techniques used to identify behavioral patterns of offenders.

What is the exchange principle?

The notion that a perpetrator of a crime will bring something into the crime scene and leave with something from it.

What scientific technique is used to analyze gunshot residue?

Scanning Electron Microscopy (SEM).

What does the term 'class evidence' mean?

Items that can be traced back to a group but not to a single source.

What does 'individual evidence' imply?

Evidence that can be linked to a unique, specific source.

What type of evidence can lead to a conviction in court?

Individual evidence, as it points to a specific suspect.

Which bone is primarily used to estimate age in skeletal remains?

The pelvic bone.

What indicates that a body has been moved after death?

Inconsistent livor mortis patterns.

What are the warning signs of heroin use?

Track marks, needle marks, drowsiness.

At what temperature does rigor mortis typically begin?

Approximately 2-4 hours after death.

How long does it usually take for rigor mortis to fully develop?

12 hours after death.

What is a critical factor concerning eyewitness testimony?

It can be unreliable and subject to errors.

What is a blowfly's role in forensics?

To estimate the time of death and assist in determining PMI.

What skin color is typical in CO poisoning?

Cherry red.

Why is the sequence of crime scene processing important?

To ensure thorough evidence collection and preservation.

What key feature can be analyzed for ancestry in skeletal remains?

Skull characteristics.