Chapter 15-Biological Stain Analysis
DNA
A biopolymer that is composed of nucleic acids, sugars, and phosphates
Antigen
A chemical with a specific structure, usually a protein, that stimulates an immune system response
Thermalcycler
A machine that controls the reaction temperature of a PCR solution
Electrophoresis
A method for separating DNA by the size of the pieces, uses electricity to attract DNA from one side to the other
Tandem repeat
A non-coding section of the DNA with repeating nucelotide sequences (e.g. AGAA), that repeat a whole number of times
Thymine
A nucelotide that pairs with adenine
Guanine
A nucleotide that pairs with cytosine
Cytosine
A nucleotide that pairs with guanine
Adenine
A nucleotide that pairs with thymine
Prostate specific antigen
A protein created by the prostate and found in seminal fluid, can be detected using an antibody-antigen test
Antibody
A protein with a specific structure, designed to attack and neutralize antigens
ABO
A series of antibodies and antigens that are related to blood type
Primer
A short piece of DNA that directs a polymerase to the DNA marker or allele to copy
Gene
A specific section of the DNA polymer that tells the body how to make proteins
Precipitin test
A technique for performing antibody-antigen reactions using a glass tube with two layers of liquids
Gel diffusion
A technique for performing antibody-antigen reactions using scientific gelatins to control the flow of materials together
Acid phosphotase
An enzyme found in high concentrations in seminal fluid, presumptive test turns purple
Polymerase
An enzyme that makes new copies of partly double stranded DNA polymers
Multiplexing
Analyzing more than one DNA marker in the same reaction
Buccal cells
Cells from the inside of the cheek
Hemastix
Commercial product containing tetramethylbenzidine, positive peroxidase-like test is blue-green
Kastle-Meyer
Contains phenolphthalein, positive peroxidase-like test is pink
DNA Sequencing
Determining the exact order of nuclotides in a DNA sequence, very time consuming
Touch DNA
Epithelial cells left behind on objects touched
CODIS
FBI maintained database for DNA profiles; each profile is 13 STRs plus amelogenin
Semen
Fluid-like material created by the male organs
Amelogenin
Gene for tooth enamel that is used for genetic sex determination in PCR testing
Heterozygous
Having two different versions of a gene, allele or DNA marker
Homozygous
Having two of the same gene, allele or DNA marker
White blood cells
Immune system cells that contain nuclear DNA
Seminal fluid
Liquid portion of semen, contains water and other proteins
Epithelial cells
Outer layer of skin cells
Red blood cells
Oxygen carrying cells that contain iron
PCR
Polymerase chain reaction
Luminol
Positive peroxidase-like test glows blue in the dark
Peroxidase-like reaction
Presumptive blood test; iron in blood reacts with peroxide and a dye to produce a colored reaction
Allele
Refers to a specific location in the DNA (chromosome and position) where a DNA sequence can be found
Short tandem repeat
Shorter length tandem repeats that are used for DNA profiling
Mitochondria
Small biological power plants found in cells, contain their own DNA code
Low copy number
Small quantities of DNA recovered from objects, PCR can amplify
Mitochondrial DNA
Small, circular DNA sequence that is maternally inherited
Sperm
Solid portion of semen, containing male genetic material
Plasma
The fluid portion of blood
Nucleotide
The individual monomer units that make up the DNA polymer
Agglutination
The reaction between antibodies and antigen containing cells, causing the cells to clump together
Chromosome
A tightly wound package of DNA polymer that can be found inside the cell nucleus