BSFS Forensic Biology and DNA Analysis

Question 1

Which technique is considered the gold standard for forensic DNA profiling in the United States today?

Accepted Answer

Short tandem repeat (STR) analysis

Answer

Restriction fragment length polymorphism (RFLP)

Answer

Mitochondrial DNA sequencing

Answer

Y-chromosome typing only

Question 2

CODIS, the national DNA database used by forensic labs in the U.S., stands for:

Accepted Answer

Combined DNA Index System

Answer

Criminal Offender DNA Identification System

Answer

Centralized DNA Observation and Indexing System

Answer

Comprehensive Offender Database and Identification System

Question 3

The presumptive test for semen that detects the enzyme acid phosphatase is known as:

Accepted Answer

AP spot test (acid phosphatase test)

Answer

PSA ELISA test

Answer

Brentamine Fast Blue test

Answer

Luminol test

Question 4

Polymerase chain reaction (PCR) is used in forensic DNA analysis primarily because it:

Accepted Answer

Amplifies small or degraded DNA samples into quantities sufficient for analysis

Answer

Directly identifies the sequence of nucleotides without amplification

Answer

Stains DNA bands for gel electrophoresis

Answer

Creates a physical cast of chromosomal structure

Question 5

Mitochondrial DNA (mtDNA) analysis is preferred over nuclear STR typing when:

Accepted Answer

Evidence such as hair shafts without roots or aged bones contains insufficient nuclear DNA

Answer

A rapid result is needed in under an hour

Answer

The suspect is male and Y-STR typing is not available

Answer

The sample contains a mixture of two contributors

Question 6

The ABO blood typing system classifies blood based on the presence of:

Accepted Answer

Specific antigens on the surface of red blood cells

Answer

Antibody levels in plasma only

Answer

The shape of red blood cells

Answer

The concentration of hemoglobin in the sample