AP Bio ch. 20
Genetic profile?
"DNA fingerprint"
A single human gene, for example, might constitute only for what?
1/100,00 of a chromosomal DNA molecule.
DNA Microarray assays?
A method to detect and measure the expression of thousands of genes at one time.
Reverse transcriptase-polymerase chain reaction?
An enzyme encoded by some certain viruses (retroviruses) that uses RNA as a template for DNA synthesis.
genome-wide association studies?
Association mapping that uses marker loci throughout the entire genome.
Nucleic acid hybridization?
Base pairing between a gene and a complementary sequence on another nucleic acid molecule.
Recombinant DNa
Dna molecules formed when segments of DNA from two different sites are combined in vitro
Short tandem repeats?
Short sequence that gets repeated many times
Vector?
Transmits the virus
RNA interference?
a biological process in which RNA molecules inhibit gene expression, typically by causing the destruction of specific mRNA molecules.
electroporation?
a brief electrical pulse applied to a solution containing cells creates temporary holes in their plasma membranes, through which DNA can enter
Expression vector?
a cloning vector that contains a highly active bacterial promoter just upstream of a restriction site where the eukaryotic gene can be inserted in the correct reading frame.
Bacterial artificial chromosome?
a large plasmid that has been trimmed down and can carry a large DNA insert, another type of vector used in DNA construction
Restriction site?
a particular short DNA sequence.
To clone pieces of DNA in the lab, researchers first obtain what?
a plasmid and then insert DNA from another soure into it.
Stem cell?
a relatively unspecialized call that can both reproduce itself indefinitely and, under appropriate conditions, differentiate into specialized cells of one or more types.
Single nucleotide polymorphism?
a single base-pair site where variation is found in at last 1% of the population
Northern blotting?
a technique that enables specific nucleotide sequences to be detected in samples of mRNA
What happens in polymerase chain reaction?
any specific target segment within one or many DNA molecules can be quickly amplified in a test tupe
Sticky end?
at least one single stranded end that has been cut up
the cDNAs that are cloned make up a what?
cDNA library
Complementary DNA (cDNA)?
can be made from messenger, transfer, ribosomal, and other forms of RNA
pluripotent?
capable of differentiating into many different cell types.
Southern blotting?
combines gel electrophoresis and nucleic acid hybridization. it allows us to detect just those bands that include parts of the B-globin gene.
Scientists are making new ground on what?
human cloning.
In vitro?
in a test tube, culture dish, or elsewhere outside a living organism
Clones are usually stored where?
in multiwelled plastic plates, with one clone per well
Gene therapy?
introducing genes into an afflicted individual for therapeutic purposes.
DNA ligase?
joins together two separate DNA modules used mainly to help create a recombinant plasmid
PCR can do what?
make billions of copies of a target segment of DNA in a few hours.
Totipotent?
mature cells that can dedifferentiate and give rise to all the specialized cell types of the organism.
The DNA of bacterial cell is protected from the cell's own restriction enzymes by the addition of what?
methyl groups to adenines or cytosines
Medical applications of DNA technology?
one important one is the identification of human genes whose mutation plays a role in genetic diseases.
A plasmid has what?
only a small number of genes.
PCR?
polymerase chain reaction. is quicker and more selective
Genetically modified organisms?
recombinant microbes
To create a library, the researcher must now modify the cDNA by adding what?
restriction enzyme sequence at each end.
What is one historically useful application of gel electrophoresis?
restriction fragment analysis
Plasmids
small circular DNA molecules that replicate separately from the bacterial chromosome.
In vitro mutagenesis?
specific mutations are introduced into a cloned gene, and then the mutated gene is returned to a cell in such a way that it disables ("knocks out") the normal cellular copies of the same gene.
Gel electrophoresis?
technique used to compare DNA. uses a gel made of a polymer.
Nucleic acid probe?
the complementary molecule, a short, single stranded nucleic acid that can be either RNA or DNA
Genomic library?
the complete set of plasmid-containing cell clones, each carrying copies of a particular segment from the initial genome.
Genetic engineering
the direct manipulation of genes for practical purposes
Who was Dolly?
the first clone- a lamb. she was euthanized at age 6 b/c of a lung disease
Reproductive cloning?
the goal of the production of new individuals
Transgenic?
the introduction of a gene from an animal of one genotype into the genome of another.
Biotechnology
the manipulation of organisms or their components to make useful products.
Cloning vector
the original plasmid, a DNA molecule that can carry foreign DNA into a host cell and replicate there
Gene cloning?
the production of multiple copies of a single gene
What did F. C. Steward accomplish with his students at Cornell?
the successful cloning of whole plants from single differnetiated cells
Why are bacterial plasmids widely used as cloning vectors for several reasons?
they can be readily obtained from commercial suppliers, manipulated to form recombinant plasmits by insertion of foreing DNA and then introduced into bacterial cells.
How id DNA microarray assays done?
tiny amounts of a large number of single stranded DNA fragments representing different genes fixed to a glass slide in a tightly spaced array or grid.
What two basic purposes is gene cloning useful?
to make copies of or amplify and to isolate copies of a cloned gene from bacteria for use in basic research
In Situ Hybridization
uses fluorescent dyes attached to probes to identify location of specific mRNAs in place in intact organism
Restriction fragment length polymorphism?
variations in DNA sequence among a population
Restriction enzymes
were discovered in the late 1960s. They protect the bacterial cell by cutting up foreign DNA from other organisms.