Missouri Crime Laboratory Analyst
Examination Practice Test Questions With
Correct Answers (Verified Answers) Plus
Rationales 2026 Q&A | Instant Download Pdf
1. What is the primary purpose of maintaining a proper chain of
custody in forensic evidence handling?
A. To increase laboratory efficiency
B. To ensure evidence admissibility in court
C. To reduce analysis time
D. To assign evidence ownership
Answer: B
Rationale: Chain of custody documents every transfer and handling of
evidence to ensure its integrity, authenticity, and admissibility in legal
proceedings. Without it, evidence may be ruled unreliable or
inadmissible.
2. Which DNA region is most commonly used in forensic
identification?
,A. Coding regions of genes
B. Mitochondrial RNA
C. Short Tandem Repeats (STRs)
D. Ribosomal DNA
Answer: C
Rationale: STRs are highly variable between individuals, making them
ideal for forensic DNA profiling and identification.
3. What is the main function of a gas chromatograph in forensic
laboratories?
A. Measuring blood pH
B. Separating volatile compounds
C. Imaging fingerprints
D. Detecting DNA mutations
Answer: B
Rationale: Gas chromatography separates volatile substances in a
mixture, commonly used in drug and arson analysis.
4. Which principle explains that every contact leaves a trace?
A. Locard’s Exchange Principle
,B. Heisenberg Principle
C. Bernoulli’s Principle
D. Hardy-Weinberg Principle
Answer: A
Rationale: Locard’s Exchange Principle states that physical contact
between two surfaces results in mutual transfer of material.
5. What is the primary goal of forensic quality assurance programs?
A. Reduce staffing costs
B. Ensure consistent and reliable results
C. Increase sample throughput only
D. Eliminate laboratory accreditation
Answer: B
Rationale: Quality assurance ensures accuracy, reliability, and
consistency of forensic analyses through standardized procedures.
6. Which technique is best for visualizing latent fingerprints on porous
surfaces?
A. Superglue fuming
B. Ninhydrin application
, C. Dusting powder
D. Electrostatic lifting
Answer: B
Rationale: Ninhydrin reacts with amino acids in fingerprints,
producing a visible purple-blue color on porous materials like paper.
7. What is the primary purpose of a control sample in forensic
analysis?
A. Increase reaction speed
B. Provide a comparison standard
C. Replace missing evidence
D. Alter test outcomes
Answer: B
Rationale: Control samples ensure that test results are accurate by
providing known reference standards.
8. Which instrument is commonly used to identify unknown
substances based on mass-to-charge ratio?
A. Microscope
B. Spectrophotometer
Examination Practice Test Questions With
Correct Answers (Verified Answers) Plus
Rationales 2026 Q&A | Instant Download Pdf
1. What is the primary purpose of maintaining a proper chain of
custody in forensic evidence handling?
A. To increase laboratory efficiency
B. To ensure evidence admissibility in court
C. To reduce analysis time
D. To assign evidence ownership
Answer: B
Rationale: Chain of custody documents every transfer and handling of
evidence to ensure its integrity, authenticity, and admissibility in legal
proceedings. Without it, evidence may be ruled unreliable or
inadmissible.
2. Which DNA region is most commonly used in forensic
identification?
,A. Coding regions of genes
B. Mitochondrial RNA
C. Short Tandem Repeats (STRs)
D. Ribosomal DNA
Answer: C
Rationale: STRs are highly variable between individuals, making them
ideal for forensic DNA profiling and identification.
3. What is the main function of a gas chromatograph in forensic
laboratories?
A. Measuring blood pH
B. Separating volatile compounds
C. Imaging fingerprints
D. Detecting DNA mutations
Answer: B
Rationale: Gas chromatography separates volatile substances in a
mixture, commonly used in drug and arson analysis.
4. Which principle explains that every contact leaves a trace?
A. Locard’s Exchange Principle
,B. Heisenberg Principle
C. Bernoulli’s Principle
D. Hardy-Weinberg Principle
Answer: A
Rationale: Locard’s Exchange Principle states that physical contact
between two surfaces results in mutual transfer of material.
5. What is the primary goal of forensic quality assurance programs?
A. Reduce staffing costs
B. Ensure consistent and reliable results
C. Increase sample throughput only
D. Eliminate laboratory accreditation
Answer: B
Rationale: Quality assurance ensures accuracy, reliability, and
consistency of forensic analyses through standardized procedures.
6. Which technique is best for visualizing latent fingerprints on porous
surfaces?
A. Superglue fuming
B. Ninhydrin application
, C. Dusting powder
D. Electrostatic lifting
Answer: B
Rationale: Ninhydrin reacts with amino acids in fingerprints,
producing a visible purple-blue color on porous materials like paper.
7. What is the primary purpose of a control sample in forensic
analysis?
A. Increase reaction speed
B. Provide a comparison standard
C. Replace missing evidence
D. Alter test outcomes
Answer: B
Rationale: Control samples ensure that test results are accurate by
providing known reference standards.
8. Which instrument is commonly used to identify unknown
substances based on mass-to-charge ratio?
A. Microscope
B. Spectrophotometer
