DNA Vocab

DNA   :- the molecules carrying the body's genetic information 

 chromosome  :-  a rod like structure in the cell nucleus along which the genes are located' it's composed of DNA surrounded by other material, mainly proteins 

 polymer :-   a substance composed of a large number of atoms; these atoms are usually arranged in repeating units, or monomers 

 nucleotide  :- the unit of DNA consisting of one of four bases--adenine, guanine, cystosine, or thymine--attached to a phosphate-sugar group 

 complementary base pairing  :-  the specific pairing of base A with T and base C with G in double-stranded DNA 

 proteins  :- polymers of amino acids that play basic roles in the structures and functions of living things 

 amino acids :-  the building blocks of proteins 

 human genome   :- the total DNA content found within the nucleus of a human cell; it is composed of approximately three billion base pairs of genetic information 

 replication :-   the synthesis of new DNA from existing DNA 

 polymerase chain reaction (PCR) :- a technique for replicating or copying a portion of a DNA strand outside a living cell; the technique leas to millions of copies of the DNA strand 

 primer  :- the short strand of DNA used to target a region of DNA for replication by PCR 

 tandem repeats :- a region of a chromosome that contains multiple copies of a core DNA sequence that are arranged in a repeating fashion 

 restriction fragment length polymorphisms:-   different fragment lengths of base pairs that result from cutting a DNA molecule with restriction enzymes 

 short tandem repeat  :- a region of a DNA molecule that contains short segments consisting of three to seven repeating base pairs 

 Electrophoresis  :- a technique that uses an electrical field within a gel to separate molecules by their size and charge 

 amelogenin gene:-   a genetic locus useful for determining gender 

 Y-STR's  :- short tandem repeats located on the human Y chromosome 

 mitochondria  :- small structures located outside the nucleus of a cell; supply energy to the cell; maternally inherited 

 sequencing:-   a procedure used to determine the order of the base pairs that constitute DNA 

 picogram :-  one-trillionth of a gram 

 epithelial cells  :- the outer layer of skin cells; these DNA-bearing cells often fall off or are rubbed off onto objects retrieved from crime scenes 

 Substrate control: - an unstained object adjacent to an area on which biological material has been deposited 

 buccal cells :- cells derived from the inner cheek lining 

 Multiplexing  :- a technique that simultaneously detects more than one DNA marker in a single analysis 

 Hybridization :-  the process of joining two complimentary strands of DNA to form a double stranded molecule 

 low copy number:-   fewer than 18 DNA-bearing cells 

 touch DNA:-   DNA from skin cells transferred onto the surface of an object by simple contact