Term
| General Sequence of events for Forensic Biology |
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Definition
| Event --> Sample Deposition--> Identification of Samples-->analyze-->extract-->quantitation-->amplification-->fragment analyis --> profile interpretation-->statistics-->reporting |
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Term
| 3 main stages in forensic biology history |
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Definition
1. antigen polymorphism
2. protein polymorphism
3. DNA polymorphism |
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Term
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Definition
-1900
-Developed the ABO blood group system which puts individuals in groups (aka forensic hemogenetics)
-Antigen polymorphism marker |
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Term
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Definition
-1915
-Paternity case resolved using ABO |
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Term
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Definition
-Standard in forensic labs, antigen polymorphism
-Absorption-inhibition ABO typing technique
-Other groups and soluble serum protein markers used
-Limited by amount and environmental degradation – so it’s not good for crime scene use |
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Term
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Definition
- Molecular biology developments leading to actual examination of DNA sequences
-Restriction enzymes, Sanger sequencing, and Southern blotting |
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Term
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Definition
| -DNA polymorphisms detected using Southern blot |
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Term
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Definition
| -Analysis of first highly polymorphic locus reported |
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Term
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Definition
-PCR: Specific DNA regions could be amplified, became the basis for DNA procedures
-Conceptualized by Kary Mullis (Cetus Corp) who got the Nobel Prize for Chemistry in 1993
-Increased sensitivity, don’t need as much DNA
-Analysis of degraded DNA was possible
-Possibility for any polymorphism in genome to be analyzed |
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Term
| History-1984 Sir Alec Jeffreys |
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Definition
-Sir Alec Jeffreys & the DNA Fingerprint
-Forensic application of VNTR loci
-Extract DNA-->Cut with restriction enzymes-->Gel electrophoresis-->Southern blotting-->Probe hybridization
-Result: Series of black bands on X-ray representing fragment length
-Very discriminating but you don’t know any of the results until the very end
-No amplification, so you needed mLs of blood |
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Term
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Definition
-Required relatively large amount of DNA
-Did not work with degraded DNA
-Inter-lab-comparisons were difficult
-Time consuming and labor intensive |
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Term
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Definition
- Technology used to resolve an immigration dispute
-Depending on the country, when you left you had to prove you were related to the person(s) you were leaving with |
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Term
| History-1986-Colin Pitchfork |
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Definition
- 2 Girls, 1 killer - Colin Pitchfork was convicted in 1988
-Richard Buckland was 1st accused and confessed to killing one girl but not the other, his semen was tested and it was determined it wasn’t him
-Went to the town and did a mass screening of over 4000 adult men and no one matched
-Months/years later a man ragged about giving a sample for a friend and told who it was (Colin P.) |
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Term
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Definition
-1987
– proficiency/competency was questionable
-Increased standardization and quality control
-Accreditation of Laboratories & Personnel and Proficiency Testing
-Forensic DNA accepted as robust and reliable forensic tool worldwide |
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Term
| Four Most Common Cell Types |
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Definition
| White blood cells, Spermatozoa, Epithelial cells, Hair follicles (all are nucleated) |
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Term
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Definition
-Usually collected using sterile swabs and moistened with sterile distilled water
-Scrapings or cutting material may also be appropriate
-Lifting from surfaces using high quality adhesive tape |
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Term
| Collection of Liquid Blood |
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Definition
-Collected via syringe (if from person) and stored in purple cap EDTA tube which prevents coagulation
-Swab or absorbent FTA paper (at crime scene)
-Air dried and stored in paper container to prevent microbial activity |
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Term
| Evidence Collection for Sexual Assaults |
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Definition
-collect ASAP!!
-Sexual assault examiner SANE
-Semen received on swabs
-Fingernail scrapings collected on swabs
-Combed pubic and head hair stored in envelopes
-Contact/bite mark samples collected on swabs |
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Term
| General Evidence Storage Procedures |
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Definition
-Always store samples in case the victim wants to press charges
-Slow rate of DNA degradation
-Low temperature and low humidity
-Limits action of bacteria/fungi that degrade biological material |
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Term
| Evidence Storage of Swabs |
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Definition
| Dried at RT and stored at RT or refrigerated or frozen – in accordance with SOPs |
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Term
| Evidence Storage for Liquid Blood |
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Definition
| Blood samples usually stored refrigerated in EDTA Tubes |
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Term
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Definition
-Blood and buccal cards, they are designed for RT storage
-They are treated with chemicals that bind DNA and prevent degradation |
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Term
| Evidence Storage of Clothing |
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Definition
-Stored in cool dry room in paper container
-Avoid moisture buildup and sample degradation |
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Term
| Evidence Storage of DNA extracts |
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Definition
| -refrigerated or frozen, varies with technique but typcially refrigerated |
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Term
| Evidence Storage of Amplified Product |
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Definition
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Term
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Definition
-typically in some sort of squad car
-needs to be documented properly in COC (conditions of storage, environment, amount of time, etc) |
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Term
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Definition
| the science that deals with the properties and reactions of serums, especially blood serum |
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Term
| Forensic Biology (definition) |
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Definition
| identification and characterization of body fluids and body fluid stains to assist in the investigation, answer questionst hat are of interest to law enforcement, and establishment of facts in a court of law |
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Term
| Importance of Forensic Biology |
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Definition
determines the source of DNA evidence and establishes a "probative area" for testing.
-reduces the rising cost of DNA analysis |
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Term
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Definition
| blood, semen, saliva, urine, and feces |
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Term
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Definition
-indicates the presence of something
-very sensitive but NOT very selective
-if positive, further testing is required
-if negative, no further testing is required |
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Term
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Definition
| confirms the presence of something and is very specific (but often not very sensitive) |
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Term
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Definition
-testing will give a positive result
-acts as a reagent performance check |
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Term
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Definition
-positive result when it should be negative
-hapens when there is high sensitivity but low selectivity
-may happen when there is a reaction with the chemicals
-happens more with presumptive, not really with confirmatory |
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Term
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Definition
-testing will give a negative result
-acts as a reagent contamination check-proves sample gave result, not the reagents
-just use water and paper, etc. |
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Term
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Definition
-negative result when should be positive
-happens when there is low sensitivity and high selectivity. |
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Term
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Definition
-info about the crime is needed to plan examination
-look at COC, case submission forms, examination request form, recieved evidence, admission labels and seals |
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Term
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Definition
-identify the probative samples (the most intimate sample is usually the best one to use)
-only use 1/3 of the evidence for testing
do unks before references so references don't contaminate the sample |
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Term
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Definition
-most common form of biological evidence
-fluid connective tissue
-8% of body weight
5-6 L in average male, 3-4 in female
-can swallow a pint before becoming ill |
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Term
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Definition
-transportation of O2, CO2, nutrients, wastes, hormones, and enzymes
-regulate pH, temperature, water
-protection against blood loss with clotting mechanisms
-protection against invading pathogens (WBC) |
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Term
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Definition
-make up 45% of blood
-Erythrocytes, globin, heme |
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Term
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Definition
-part of formed elements of blood
-biconcave anucleate disks, responsible for gas exchange
-4.5-6 x 10^6/ mm^3
-lose the nucleas before going into the circulatorys ystem
-red blood cells
-source of hemoglobin in blood stains and produce serological test results |
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Term
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Definition
-globin with 4 polypeptide chains (2 alpha, 2 beta) and each has a heme group with a single O2 binding site
-thousands per erythrocyte
-makes up 33% of living RBC and 95% of dried (weight) |
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Term
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Definition
| occurs when CN and/or CO2 bind to heme. |
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Term
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Definition
-a formed element of blood
-5 types: lymphocytes, monocytes, nutrophils, basophils, and eosinophils
-involved in phagocytosis, antibody production, and immune response
-5000-10000/mm^3, larger and ferwer than RBC
-amoeboid nucleated white blood cells
-where you find genomic DNA, produces genotypes
-NOT important in forensic biology testing |
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Term
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Definition
-1869
-performed the 1st extract of DNA w/ WBC which lead to the discovery of DNA
-his techniques are the foundation of extractions today |
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Term
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Definition
-part of formed elements of blood
-small cell fragments of megakaryocyte-not true cells!
-platelets, involved in clotting
-20000-400000/ mm^3 |
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Term
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Definition
-55% of blood
-liquid portion of blood which contains proteins, nutrients, salts, and clotting factors
Serum-plasma without clotting factors |
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Term
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Definition
-classifies individuals into blood groups based on a chemical change in blood which is permanently and genetically controlled and can be identified through analytical methods
-the specificity and binding power of antigens is used to detect human blood
-don't really use ABS system forensically because it is not unique enough |
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Term
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Definition
-no antigens
-contains A and B antibodies |
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Term
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Definition
| -has both antigens, no antibodies |
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Term
| Hematopoesis/Hematogenesis |
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Definition
-development and production of blood cells
-yolk sac-->liver-->bone marrow--> lymphatic cells
-all start from pleuripotent stem cells and undergo differentiation into lymphoid, myeloid, or erythroid cells |
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Term
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Definition
-differentiated from pleuripotent stem cells
-B cell, T cell, NK cell |
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Term
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Definition
-differentiated from pleuripotent stem cells
-neutrophil, basophil, eosinophil, dendritic cell, mast cell, macrophage, most of WBC |
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Term
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Definition
-differentiated from pleuripotent stem cells
-bone marrow, erythrocyte, megakaryocyte--> platelet |
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Term
| Presumptive Tests for Blood |
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Definition
-all simple colorimetric tests (color change indicates presence of blood)
-very sensitive (up to dilutions of 1:100000)but not selective
-based on the peroxidase activity of heme which reduces H2O2 and oxidizes a colorless compound to produce a color change
-can be chemiluminescent or fluorescent |
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Term
| False Positives in presumptive tests of blood |
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Definition
-due to peroxidase-like activity of other compounds
-chemical oxidants and catalysts such as Cu, K2SO4, KMNo4, bleach, formalin, rust
-plant material such as vegetable peroxidases found in apples, apricots, beans, beets, blackberries, cabbages, turnips
-animal sources such as bonew marrow, leukocytes, brain, spinal fluid, lung, spleen, mucus, pus, enzymes
-high heat can inactivate peroxidase activity of inhibitors removing the possibility of a false positive. |
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Term
| Generic Procedure for Presumptive Tests for Blood |
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Definition
-add a drop of the oxidizable compound, wait a few seconds to assure no color change
-add drop of 3% H2O2 and immediately observe stain for color change
-report results (+ or -) |
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Term
| Types of Presumptive Tests for Blood |
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Definition
-Phenolphthalein (Kastle-Meyer)
-Tetramethylbenzidine
-leucomalachite Green
-Luminol (3-amino-hthalhydrazide)
-fluorescein |
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Term
| Phenolphthalein/Kastle-Meyer Reagent |
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Definition
-a presumptive blood test
-sensitive and specific, less false positives than others
-reduced(colorless)-->Heme/OH--> Oxidized state (pink)
-need to read in less than a minute, false positives are usually the wrong color pink |
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Term
| Tetramethylbenzidine (TMB) |
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Definition
-a presumptive blood test
-very sensitive but not very specific
-high amount of false positives and no false negatives
-reduced (colorless)--> heme/OH--> oxidized state (blue-green)
-not the safest, carcinogenic |
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Term
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Definition
-a presumptive blood test
-sensitive and specific
-reduced(colorless)-->heme/OH--> oxidized state (Green) |
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Term
| 3-amino-phthalehydrazide (Luminol) |
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Definition
-used for invisible bloodstains which give a bluish-white chemiluminescence
-very sensitive (1:5000000-10000000) but not very specific (bleach will react)
-better for horizontal surfaces
-don't need to illuminate but you do need a dark room, lasts only about 30 seconds
-a presumptive blood test
-heme accelerates the oxidation of luminol, catalytic |
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Term
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Definition
-a presumptive blood test
-fluorescin--> fluorescein (fluorescence)
-NOT catalytic
-used for invisible bloodstains which fluoresce under UV illumination
-sensitive (1:1000000) and more specific than luminol
-better for vertical surfaces
-needs UV illumination at 425-485 nm with an ALS |
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Term
| Types of Confirmatory Tests for Blood |
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Definition
-Microscopic
-spectrophotometric
-microcrystalline tests (ferroprotoporphyrin, teichman, takayama)
-immunological tests (hematrace |
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Term
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Definition
-more specific than presumptive tests (fewer false +/-) but not as sensitive (need more sample)
-negative result isn't necessarily the absence of blood
-might go straight to DNA and skip confirmatory test if you've done a quantification step already specific for humans and higher primates |
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Term
| Microscopic Confirmatory Tests for Blood |
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Definition
| -erythrocytes and leukocytes |
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Term
| Spectrophotometric Confirmatory Tests for Blood |
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Definition
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Term
| Microcrystalline Tests for Blood |
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Definition
-confirmatory test
-formation of hemoglobin derivative crystals
Ferroprotoporphyrin, Teichman and Takayama Tests |
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Term
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Definition
-microcrystalline confirmatory test for blood
-binds nitrogen containing compounds and reacts with the non-protein, heme portion
-forms hemoglobin derivative crystals
-good with ~0.001mL of blood and 20 year old stains |
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Term
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Definition
-microcrystalline confirmatory test for blood
-halide- glacial acetic acid + heme --> hematin derivative
-rhomboid, brown crystals
-need heat, and over/under heating produces a false negative |
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Term
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Definition
-microcrystal confirmatory test for blood
-NaOH + dextrose + pyridine --> insoluble crystal product in the form of furry, red crystals
-overheating does not produce false negatives
-can add DTT for older stains and it increases the rate of crystal formation by binding with any oxygen present which competes with the pryimidines
-more sensitive and doesn't undergo the same issues with application |
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Term
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Definition
-chromatographic immunoassays that are quicker, easier, and similar to pregnancy tests
-ABAcard HEMATRACE is commonly used
-human specific, but higher primate and ferret blood will react
-antigen-antibody interactions |
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Term
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Definition
| stimulates the immune response in a host and is recognized by an antibody |
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Term
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Definition
immunoglobulin with a receptor that forms in response to antigens
-bonds form between the epitopes of antigen and the antibody
-cross reactions can occur when the antibody can bind to more than one antigen |
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Term
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Definition
-more specific, only reacts with a single antigen
-prepared by harvesting spleen cells from a host innoculated with the antigen. The spleen cells are fused with myoloma cells t produce a hybridoma. Only a few hybridomas form right and they are selected and can make antibodies forever!
-major limitation is that you need a highly conserved antigen for testing and it must be identical on everyone and everyone must have it. |
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Term
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Definition
-mobile Hb antibody-dye conjugates in sample well bind to hemoglobin present and form mobile antigen-antibody complexes
-the mobile antigen-antibody complexes travel down to immobilized antihuman Hb antibodies in the test area which will bind the mobile complex in an antigen-antibody-antigen sandwich
-if [Hb] is above the threshold, a pink line will result that is positive for blood
-unbound mobile antihuman Hb antibody-dye conjugates bind to immobilized antihuman antibodies in control region and a pink line means its working
-h-bonds, hydrophobic bonds and VDW bonds |
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Term
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Definition
-false negative with hematrace
-concentration of blood is too high and free Hb will reach the test area and the immobile antibody will become saturated with Hb (Hb is smaller and faster)
-no binding of antigen-antibody-dye conjugate occurs and results appear negative |
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Term
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Definition
| -visual exam, tactile exam, stereomicroscope exam, ALS illumination |
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Term
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Definition
-always use PPE and universal precautions
-allow wet stains to dry for long term storage
-conserve some of the stain for additional testing
-store in paper containers
-collect controls when appropriate |
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Term
| Scraping (of bloodstains) |
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Definition
-no sample dilution
-easy storage
-causes flaking, can be difficult depending on the substrate |
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Term
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Definition
-no sample dilution
-minimal contamination and easy storage
-can't always cut everything and you can get interference from substrate. |
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Term
| Wet Swabbing (of blood stains) |
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Definition
-concentrate sample on to small surface
-dilution of sample and potential contamination |
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Term
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Definition
-concentrates sample on small surface, no dilution
-yield is low for a dry stain and potential contamination. |
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Term
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Definition
-viscous, slightly yellowish fluid/glandular secretion
-forensically important part is AP and PSA
-pH is 7.2-8.0 (neutralizes vaginal pH)
-80-90% H20
-8-10% sperm (organic component)
-2-6% proteins
-1-2% salt
-0.21% lipids
Cellular portion: sperm, WBC, epithelial cells
-Liquid Portion: accessory gland secretions and glycoproteins (AP and PSA) |
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Term
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Definition
-average male -3 mL (300 million sperm) or about 1/5 tblspoon
-1-6 mL range
-40% of sperm will be abnormal
-varies depending on interval since last ejaculate, metabolic activity of glands, physiological conditions, male reproductive system. |
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Term
| Two Fragments of Ejaculate |
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Definition
1st: sperm + prostatic fluid, set up for genetic protection and meant to fertilize
2nd: seminal vesicle secretions, few sperm, poor environment for survival of sperm (may be to act as a barrier so their stuff goes in and other males can't fertilize) |
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Term
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Definition
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Term
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Definition
| located in the testes, storage and development of sperm, where gametes are produced |
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Term
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Definition
-coiled tubule on the testes -connects the testes to the vas deferens
-gives about 5% of ejaculate |
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Term
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Definition
-transports sperm to the urethra
-on either side of pubic bone and lies on urinary bladder |
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Term
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Definition
| -transports semen/urine from the accessory gland out of the body, undergoes parastolysis (muscle contractions) that are autonomic |
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Term
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Definition
-secretes fluid rich in fructose (energy for sperm) and is ~60% of sperm
-opens into the vas deferens as it enters the prostate gland
-slightly yellow in color because of the epithelial cells
-has basic pH
-part of the secretions are proteins which play a role in coagulation (flavin-fluoresces) |
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Term
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Definition
-urethra and vas deferens are in it, secretes alkaline fluid into the urethra
-~13-33% of volume
-secretes acid phosphoatase and PSA (use in identifiaction of semen samples)
-high in zinc which prolongs the life of the sperm |
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Term
| Bulbourethral Gland/Calper's Gland |
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Definition
-secretes a viscous pre-ejaculate that neutralizes the acidity of the urethra and lubricates it
-flushs out the urine and any foreign matter
-5% of ejaculate |
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Term
|
Definition
| -swollen portions of the vas deferens that secrete a yellowish fluid |
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Term
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Definition
-ovoid shape that is 4.6 microns long, 2.6 microns wide and 1.5 microns thick
-packed with chromatin and nucleus (chromatin is 6x as condensed)
-dyes red (except for acrosomal cap) |
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Term
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Definition
-found on the head of sperm
-rich in enzymes which penetrate the cell membranes of the egg cell
-takes ~100 sperm acting on the same point to penetrate
-dyes whitish/pink |
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Term
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Definition
-10-15 mitochondrial spires which provide energy
-dyes blue |
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Term
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Definition
-axial filament that serves as the motor apparatus
-dyes green
-makes up ~90% of length along with midpiece
-can move 1-3mm/min, reaches its max speed in very acidic environments
-total sperm length is 50-60 microns (about 420 sperm = 1 in) |
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Term
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Definition
-Development: spermatogenesis occurs in the semniferous tubules and it takes about 70 days to get to the mature state
-Storage: in the semniferous tubules in the epididymus
-Maturation: occurs in epididymus
-Transportation: from the epididymus to vas deferens and then from the ejaculatory duct to the urethra
-Vaginal Cavity: an acidic environment
- can live up to 72 hours, 96 hours is rare
- might last longer in deceased individuals
- shorter time frame in anal cavity
- motility is lost in 3-6 hours post ejac in vagina
-Fabric: allowed to dry and stored, 28 years storage |
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Term
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Definition
-typically 10^7 to 10&6 sperm per mL of semen
-over 100 million sperm produced a day
-drugs and alcohol reduce the amount of sperm
-decreased by vasectomy, castration, oligozoospermia, infertility, and aspermia |
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Term
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Definition
| the vas deferens is severed and spermatozoa disintegrate |
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Term
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Definition
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Term
|
Definition
| abnormally low sperm count of less than 20x10^6 /ml |
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Term
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Definition
| -abnormally low sperm count of less than 50 million/ ml |
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Term
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Definition
sterile, no sperm
-doesn't affect secretion of seminal fluid |
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Term
|
Definition
| -ALS, Seminal Acid Phosphatase, Christmas Stain, PSA |
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Term
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Definition
-semen stains aren't always visible but glow bluish/white under illumination with UV at 450-495 nm, using amber goggles
-screening tool and presumptive, just facilitates searching
-more intense illumination than other bodily fluids
-the substrate will affect the glow |
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Term
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Definition
-not affected by vasectomies
-has a half-life of 6 mo, reduced in wet environments
-can test up to a year if frozen
-produced in prostate gland and seminal vesicles
-seminal AP is decreased in vagina because of dilution and degradation
-significant levels begin at puberty (~15-40)
-it is a glycoprotein dimer 100-120 kDa that hydrolyzes phosphorylcholine to phosphate and choline
-detectable up to 72 hours in the vagina
-water soluble, washing clothes will remove it |
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Term
| Sources of Acid Phosphatase |
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Definition
-other acid phosphatases can interfere (specifically vaginal secretions)
-vaginal secretions, human milk, fecal material, RBC, urine
-fungi, bacteria, brussle sprouts, cauliflower, sweet almonds, rice bran, lucern seeds, clover, bind weed, snake poisons |
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Term
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Definition
-brentamine blue (colorless diazonium dye) reacts with alpha-naphthyl phosphate and cleaves the alpha-nap, making an insoluble, pigmented diazonium alpha-nap compound
-postive = purple color change
-negative= no color change
-highly sensitive (can detect 1:500 dilutions)
-not very specific (any AP present reacts)
-can be used to map a stained area
-reagents are light sensitive and need to be stored in the dark in a fridge and must be discarded after 7 days. |
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Term
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Definition
-confirmatory test
-cutting from sample is rubbed onto moistened slide and slide is dried on a slide warmer
-nuclear fast red stain/Kernictrot Stain is added and allowed to stain for 15 mins
-rinse with distilled water
-stain with picroindigocarmine staining for 15 seconds(too long will cause overstaining)
-rinse with ethanol
-add permel to the slide and a slide cover and do sperm ID under microscope
-epithelial cells will dye green with a red nucleus but are blobish |
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Term
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Definition
+4= many sperm in every field
+3= many or some in most fields
+2= some sperm, easy to find
+1= some sperm, hard to find
few=small number on slide
0= no sperm on slide
-record presence of tails |
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Term
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Definition
-look under microscope at greater than 10x
-varies with deposition
-intact tail= recent encounter (gives TSI)
-40% are malformed
-in vagina expect to see heads 3-7 days later
-2-3 days later in anus and 6-24 hours later in oral cavity you can still see heads
-intact tail can be found 0-26 hours after intercourse in vagina, rarely seen in others after 5 hours |
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Term
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Definition
| -give a similar appearance as sperm in christmas tree staining, but are darker red |
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Term
| Prostate Specific Antigen (PSA/P30) |
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Definition
-confirmatory test for sperm
-discovered in 1870s, test in 1990s
-glycoprotein from epithelial lining of prostate
-other bodily fluids have a low amount below forensic detection (breast milk, female urine, amniotic fluid, sweat) |
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Term
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Definition
| -determined the forensic relavence of PSA in 1978 |
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Term
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Definition
-immunochromatographic assay (like hematrace)
-mobile monoclonal antihuman PSA antibody-dye conjugate used
immobilized polyclonal antihuman PSA antibody in test area binds to the mobile antigen-antibody complex and gives a pink band if there is more than 4 ng/mL.
-control region used for QC (antiglobulin recognizes the mobile antihuman PSA antibody)
-high dose hook effect can occur (antigens move more quickly and get to control first)
-might not have to do p30 if AP is positive, depends on SOP, backlog, etc |
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Term
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Definition
-has little forensic importance for FB, but it is fairly easy to get a full DNA profile from it
-until recently there was no confirmatory test for saliva
-colorless, slightly viscous fluid that lubricates ingested food
-it is the first digestive juice which initiates the digestion of starch (alpha-amylase)
-97-99% water with pH of 6.3-6.8
-pH increases rapidly because of absorbed bicarbonate
-there is a basal level of saliva and it increases when you eat.
-found on the AMY1/HSAA loci and seminal pancreatic fluid is found on AMY2/HPAA loci, both are on c'some 1 |
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Term
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Definition
-Sublingual: produces about 5% of saliva
-Submaxillary: produces 70% of saliva
-Parotid: produces 25% of saliva |
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Term
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Definition
-controlled reflex due to chemical and mechanical stimuli as well as visual and olfactory stimuli
-adults secrete 1-2L/day and 0.5 mL to 4 mL/minute
-submaxillary is 1/3, parotid is 1/4 and sublingual is 5/12 |
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Term
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Definition
-alkaline and acid phosphatases
-blood group antigens
-inorganic compounds: nitrites and thiocyanates
-buccal cells
-epithelium cells
-liquid secretions: serous, thin, contains amylase, water and electrolytes
-mucinous secretion: clear, viscous, a mixture of glycoproteins which have a lubricating action, good for saliva testing
-amylase |
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Term
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Definition
-the forensically important part of saliva
-alpha amylase is found in saliva 50 times more than other fluids (blood, vaginal secretions, seminal fluid, perspiration, breast milk, tears, and fecal matter)
-beta amylase is found only in plants but is indistinguishable from alpha
-amylase hydrolyzes amalose (long, unbranched) and amolopectin (highly branched) found in starch to cleave off a maltose (two glucose) at a time. |
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Term
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Definition
-presumptive test of saliva
-starch saturated paper is stained with iodine, if amylase is present the starch will be broken down and no color change will occurs
-if no amylase present, the starch will turn purple.
-you can detect amylase 28 months after deposit
-it is not human specific
-you can get a false negative if you don't make the paper right
-good for large substrates because its cheap and immediate |
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Term
| Wurster/Laux Paper/ "Press Test" |
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Definition
-presumptive test for saliva
-starch saturated filter paper is exposed to/mashed onto the saliva stain adn then treated with iodine solution
-positive will turn white
-1:128 dilution still yields a positive
-lots of false positives can occur with any type of amylase |
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Term
| Amylase Radial Gel Diffusion |
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Definition
-presumptive test for saliva
-using a starch agarose gel, the samples are applied to wells and allowed to diffuse into gel and are developed with iodine
-amylase containing areas remain clear (Because starch is broken down)
-amylase-free areas turn blue
-you can quantitate based on the diameter of clear circle
-false positives occur with any type of amylase |
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Term
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Definition
-Rapid Stain Identification of Human Saliva
-commercially produced
-first confirmatory test for saliva
-immunochromatographic, similar to hematrace (uses human salivary antigen)
-human specific to 1 microliter
-no cross reactivity with blood, semen, urine, or vag secretions |
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Term
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Definition
| regulate urine production and regulate water and salt balance as well as waste product levels |
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Term
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Definition
| transport urine to the bladder |
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Term
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Definition
| stores urine for elimination |
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Term
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Definition
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Term
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Definition
-transparent, amber fluid (urochrome pigment) which is sterile when it leaves the body
-might have epithelial cells in it that are sloughed ff on the way out
-excretion, NOT secretin, of 1-2L/day
-95% water, rest is nitrogenous wastes, electrolytes, pigments, and hormones
-develops ammonia odor from ammonium carbonate and bacterial breakdown of urea |
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Term
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Definition
-nitrogenous compound made from catabolism of amino acids
-found in urine |
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Term
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Definition
-difficult to visualize, may need ALS
-less intense than saliva and semen |
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Term
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Definition
-made from metabolism of creatine in muscle tissue and blood and excreted in urine as metabolic waste
-found in:
-urine: 2454.54 mg/day
-serum 0.6mg/ml
-saliva 0.275mg/100 ml
-sweat 0.1-0.3 mg/ml |
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Term
| Creatinine Test/Jaffe TEst |
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Definition
-presumptive test for urine
-creatinine + picric acid(yellow)--> NaOH --> Creatiine picrate (red/brown)
-control cuttings are necessary |
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Term
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Definition
| -runs from the mouth to the anus |
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Term
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Definition
-food is ground before esophagus which increases the surface area
-saliva converts starch to maltose |
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Term
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Definition
| transports food to the stomach |
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Term
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Definition
partialy digests protein creating a soup like mixture
-contains gastric juice made of pepsin and HCL |
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Term
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Definition
-involved in nutrient absorption
-contains bile and pancreatic/intestinal juices |
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Term
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Definition
-found in the small intestine
-emulsifies fat so it is more easily absorbed |
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Term
| Pancreatic/Intestinal Juice |
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Definition
| -converts starch to maltose, fats to fatty acids and glycerols, and proteins to smaller molecules |
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Term
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Definition
| -water reabsorption (lots of water moving from small to large intestine) |
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Term
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Definition
| waste compression and stool storage for evacuation |
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Term
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Definition
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Term
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Definition
-remaining H2O and solid material from digestion as well as mucus, undigested food, and bacteria
-distinctive color/odor is due to diet, putrefactive bacteria, drugs, pathological conditions, indole skatole, and methyl mercaptin
-bacteria make up 1/3 weight of feces (can do microscopic ID of bacteria in feces) |
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Term
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Definition
-identified with or without ALS
-blood and fecal matter both turn black under ALS |
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Term
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Definition
-product of bilirubin reduction in intestines
-bilirubin is the principle bile pigment and is produced in omnivores and carnivores, NOT herbavores
-nuclear DNA testing is unsuccessful b/c of bile pigments and salts (as well as bacteria degrading DNA) |
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Term
| Presumptive Testing of Feces |
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Definition
zinc chloride in absolute ethanol
-urobilinogen + ZnCl-->EtOH-->urobilin-Zinc complex (apple green fluorescence) |
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Term
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Definition
-four protoporphyrin molecules with a central iron atom
-Fe2+ in fresh blood and Fe3+ in dried |
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