Biological Evidence Flashcards
1
Q
presumptive tests for blood
A
- Phenolphthalein: pink, reliable
- TMB: common, false positives
- Leucomalachite green: green, eliminates DNA
- Leuco Crystal Violet: violet, sensitive
- Luminol: 30-40s illumination, suspected carcinogen, eliminates DNA
- Fluorescein: possible carcinogen
- Hemastix: rapid and sensitive
- hemident: sensitive, eliminates DNA
- bluestar: illuminance last several minutes
2
Q
confirmatory tests
A
- Takayama: red feathery crystals
- Teichman reagent: brown-yellow rhomboid crystals
- Precipitin: antisera reactions
- ABA Card: hematrace strips
3
Q
blood typing
A
- not individualized but can exclude suspects
4
Q
CODIS
A
- FBI combined DNA index system
- uses 20 loci (specific location of gene sequences)
5
Q
Blood collection
A
- Liquid - dry swab, air dry
- Dry - wet swab, air dry, unless the object is portable
6
Q
Semen
A
- Contains high levels of SAP
- Presumptive: Acriflavine - fluoresces blue
- Confirmatory: microscopic ID, P30 test for vasectomies
7
Q
Saliva
A
- Presumptive: tests for amylase, however its found in many other things
- stains not usually evident, need a cup or cigarette
8
Q
Urine
A
- Presumptive tests for creatine, also in sweat
- no confirmatory
9
Q
Vomit
A
- No presumptive or confirmatory
- determine food and pH
10
Q
Vaginal Secretions
A
- Foreign DNA compared to samples from a penis or condom
- preserved by freezing
