BSFS Forensic Biology and DNA Analysis 3

Question 1

Familial DNA searching involves:

Accepted Answer

Searching CODIS for partial matches that may indicate a biological relative of the true contributor

Answer

Familial searching looks for near-matches in DNA databases that suggest a close relative of the unknown contributor may be in the system, potentially leading investigators to the source.

Question 2

Which confirmatory test is used to identify sperm cells under a microscope in forensic biology?

Accepted Answer

Christmas tree stain (Kernechtrot-Picroindigocarmine)

Answer

The Christmas tree stain differentially stains sperm heads red and tails green, confirming the presence of intact or damaged spermatozoa microscopically.

Question 3

Forensic DNA phenotyping (FDP) refers to:

Accepted Answer

Predicting physical appearance traits such as eye color, hair color, and ancestry from DNA evidence

Answer

FDP uses single nucleotide polymorphisms (SNPs) to generate predictive information about an unknown contributor's appearance and biogeographic ancestry.

Question 4

The random match probability (RMP) in a DNA case represents:

Accepted Answer

The probability that an unrelated random person from the population would share the same DNA profile

Answer

RMP quantifies the rarity of a DNA profile by calculating how frequently that exact combination of alleles would be expected to occur by chance in the general population.

Question 5

Biological evidence should be stored long-term in which condition to best preserve DNA?

Accepted Answer

Frozen at -20°C or below in a dry state

Answer

Dry, frozen storage minimizes enzymatic degradation, bacterial activity, and oxidative damage that destroy DNA integrity over time.

BSFS - Bachelor of Science in Forensic Science Practice Test

BSFS - Bachelor of Science in Forensic Science Practice Test

BSFS Forensic Biology and DNA Analysis 3