Body Fluids

Question 1

what is forensic biology/serology?

Answer 1

study of cells and serums

Question 2

how are body fluids important to Crime Scene Investigations?

Answer 2

DNA
Forensic Toxicology

Question 3

what is DNA?

Answer 3

personal blueprint carries a genetic code that individualizes each person, except identical twins

Question 4

what is toxicology?

Answer 4

presence of drugs/alcohol in body fluids

Question 5

where are these body fluid samples collected?

Answer 5

samples taken at DUI centers/hospitals and sent to lab
samples taken at autopsy and sent to lab directly, not to CSI

Question 6

types of samples sent to lab directly

Answer 6

vitreous humor - the heartiest type of body fluid that can be found
blood-heart
urine
cerebral-spinal fluid

Question 7

what equipment is used to collect samples?

Answer 7

use gas chromatography-mass spectrometry
GCMS

Question 8

DNA types

Answer 8

DNA (nuclear DNA)
mtDNA (mitochondrial DNA)

Question 9

where is DNA found?

Answer 9

found within the nucleus of cells; therefore any fluids/tissues that have cells with nuclei will have DNA information

Question 10

who is DNA inherited from?

Answer 10

half from mom and half from dad

Question 11

where is mtDNA found?

Answer 11

found in the mitochondria in nucleated cells and on-nucleated cells (hair, fingernails)

Question 12

who is mtDNA inherited from?

Answer 12

maternally inherited
may be found in degraded samples, skeletal remains

Question 13

The Northern Virginia Forensic Laboratory does not perform ? why?

Answer 13

mtDNA analysis on routine cases​

More expensive and extensive to test​
Goes to FBI Lab

Question 14

What body fluids have DNA?

Answer 14

Semen / Seminal Fluid​
Vaginal Fluid​
Saliva​
Perspiration​
Urine​
Tears​
Body/fetal tissues​
Bones​
Hair

Question 15

Saliva, perspiration, urine, tears, etc. – not found in liquid itself, found in ?

Answer 15

epithelial cells

Question 16

where do you look for DNA?

Answer 16

Hats, caps​, Masks​, Gloves​, Socks​, Shoes​, Toothbrush, Weapons, Clothing​, Telephones​, Toilet bowl​, Sinks​, Fingernail scrapings​, Envelopes​
Think creatively!!

Question 17

what is touch DNA?

Answer 17

A deposit of epithelial cells from “touching” an object to attempt to obtain a DNA profile

Question 18

reminders when collecting DNA?

Answer 18

cross-contamination: not always a good sample bc it can be mixed from other contributors (ex: door knob)
PPE: remember to wear gloves and do not breathe onto evidence​

Question 19

what does CODIS stand for?

Answer 19

Combined DNA Index System

Question 20

what does CODIS contain?

Answer 20

FBI database containing DNA profiles of convicted felons

Question 21

two types of indexes from CODIS

Answer 21

Forensic Index
Offender Index

Question 22

what is Forensic Index?

Answer 22

profiles from crime scene evidence

Question 23

What is Offender Index?

Answer 23

profiles of convicted sex offenses and other violent crimes

Question 24

are all convicted offenders entered into the database?

Answer 24

No, every state has a different system for uploading these swabs into the system. Depends on state and crime. In state of VA, any felony crime will be uploaded to system and crime will be compared to it

Question 25

what 3 questions do we ask about blood?

Answer 25

1. is it blood? 2. is it human? 3. Who's is it?

Question 26

what is blood consisted of?

Answer 26

blood consists of plasma and cells (red blood cell, white blood cell, and platelets)

Question 27

what is the function of blood?

Answer 27

carries oxygen to cells via hemoglobin

Question 28

2 types of tests for blood

Answer 28

presumptive test confirmatory test

Question 29

what is a presumptive test?

Answer 29

field test kits, sample of suspected blood is swabbed and tested with chemical

Question 30

what is used in the presumptive test?

Answer 30

MacPhails reagent​ Phenolphthalein- (Kastle-Meyer Reagent)​ Leucomalachite green​ Orthotolidine​ Hematrace- human blood

Question 31

when shouldn't you do a presumptive test?

Answer 31

if you have a small sample

Question 32

where is the confirmatory test done?

Answer 32

done at lab

Question 33

what is the hematrace test?

Answer 33

will come back and say if it is human blood or not; it will say it is human blood if it is ferret blood

Question 33

UV/LS doesn't ? is absorbs (darkens)

Answer 33

fluoresce

Question 34

types of chemicals used for locating blood

Answer 34

lumimol fluorscein blue star

Question 35

what is luminol?

Answer 35

chemiluminescent compound, extreme sensitivity, need complete darkness, can not overspray, false positives, need PPE, reacts with bleach

Question 36

what is fluorscein?

Answer 36

needs ALS, does not react to bleach, need PPE

Question 37

what is blue star?

Answer 37

has a stronger and longer-lasting luminescence that does not require total darkness to be visible, does not alter DNA, works well on fresh, old, diluted, or altered stains

Question 38

what is seminal fluid composed of?

Answer 38

95% fluid, 5% spermatozoa, 200 million sperm

Question 39

characteristics of seminal fluid

Answer 39

fluoresces under UV/ALS light may be detected in victim body orifices for days; rape

Question 40

type of presumptive test

Answer 40

acid phosphatase test

Question 41

what does an acid phosphatase test do?

Answer 41

sample stain on swab or filter paper, turns blue/purple

Question 42

type of confirmatory test

Answer 42

prostate-specific antigen (PSA)

Question 43

What is prostate-specific antigen?

Answer 43

confirmatory test for semen

Question 44

other body fluids

Answer 44

saliva urine vaginal secretions

Question 45

where to look for saliva? urine? vaginal secretions?

Answer 45

Saliva: pillow, sink, sidewalk​ Urine: does not contain DNA, the epithelial cells do​ Vaginal: common and uncommon places look inside the victim's

Question 46

parts of urine

Answer 46

Diluted _cell__ concentrations​ Large amount of __bacteria__

Question 47

types of DNA samples from suspects

Answer 47

Blood Samples- need nurse/doctor, purple-top tubes (EDTA), need to be refrigerated​ ​Buccal_ Swab Samples​ >Two saturated buccal swabs​ >Pre-packaged kits available from the DFS Laboratory​ Hair Samples​ Clothing collection

Question 48

taken under ? or a ?

Answer 48

consent, search warrant

Question 49

VPERK

Answer 49

Victim Physical Evidence Recovery Kits

Question 50

DNA samples from victim

Answer 50

​ Blood Samples- need nurse/doctor, purple-top tubes (EDTA), need to be refrigerated​ Buccal Swab Samples​ Two saturated buccal swabs​ Pre-packaged kits available from the DFS Laboratory​ Vaginal/cervix/anal swabs/slides​ Hair Samples combs​ Clothing collection​ Fingernail scrapings/clippings​ Other Trace

Question 51

how are DNA samples collected from victim?

Answer 51

*usually taken under a consent *Don’t forget to document physical injuries​ * Rapes - need samples from all consensual partners