Chapter 20 Flashcards
A DNA molecule made in vitro with segments from different sources.
Recombinant DNA
The manipulation of organisms or their components to produce useful products.
Biotechnology
The direct manipulation of genes for practical purposes.
Genetic Engineering
A small, circular, double-stranded DNA molecule that carries accessory genes separate from those of a bacterial chromosome. They are also found in some eukaryotes, such as yeasts.
Plasmids
The production of multiple copes of a gene.
Gene Cloning
An endonuclease (type of enzyme) that recognizes and cuts DNA molecules foreign to a bacterium (such as phage genomes). The enzyme cuts at specific nucleotide sequences (restriction sites).
Restriction Enzymes
A specific sequence on a DNA strand that is recognized and cut by a restriction enzyme.
Restriction Site
A DNA segment that results from the cutting of DNA by a restriction enzyme.
Restriction Fragments
A single-stranded end of a double-stranded restriction fragment.
Sticky End
A linking enzyme essential for DNA replication; catalyzes the covalent bonding of the 3’ end of one DNA fragment (such as an Okazaki fragment) to the 5’ end of another DNA fragment (such as a growing DNA chain).
DNA Ligase
In genetic engineering, a DNA molecule that can carry foreign DNA into a host cell and replicate there. They include plasmids that move recombinant DNA from a test tube back into a cell and viruses that transfer recombinant DNA by infection.
Cloning Vector
A set of cell clone containing all the DNA segments from a genome, each within a plasmid, phage, or other cloning vector.
Genomic Library
A large plasmid that acts as a bacterial chromosome and can carry inserts of 100,000 to 300,000 base pairs.
Bacterial Artificial Chromosome (BAC)
A double-stranded DNA molecule made in vitro using mRNA as a template and the enzymes reverse transcriptase and DNA polymerase. A _____ molecule corresponds to the exons of a gene.
Complementary DNA (cDNA)
A gene library containing clones that carry complementary DNA (CDNA) inserts. The library includes only the genes that were transcribed in the cells whose mRNA was isolated to make the cDNA.
cDNA Library
A cloning vector that contains the requisite bacterial promoter just upstream of a restriction site where a eukaryotic gene can be inserted, allowing the gene to be expressed in a bacterial cell.
Expression Vector
A cloning vector that combines the essentials of a eukaryotic chromosome–an origin for DNA replication, a centromere, and two telomeres–with foreign DNA.
Yeast Artificial Chromosomes (YACs)
A technique to introduce recombinant DNA into cells by applying a brief electrical pulse to a solution containing the cells. The pulse creates temporary holes in the cells’ plasma membranes, through which DNA can enter.
Electroporation
A technique for amplifying DNA in vitro by incubating it with specific primers, a heat-resistant DNA polymerase, and nucleotides.
Polymerase Chain Reaction (PCR)
A technique for separating nucleic acids or proteins on the basis of their size and electrical charge, both of which affect their rate of movement through an electric field in a gel.
Gel Electrophoresis
A technique that enables specific nucleotide sequences to be detected in a sample of DNA. It involves gel electrophoresis of DNA molecules and their transfer to a membrane (blotting) followed by nucleic acid hybridization with a labeled probe.
Southern Blotting
A technique that enables specific nucleotide sequences to be detected in a sample of mRNA. It involves gel electrophoresis of RNA molecules and their transfer to a membrane (blotting). followed by nucleic acid hybridization with a labeled probe.
Northern Blotting
A technique for determining expression of a particular gene. It uses reverse transcriptase and DNA polymerase to synthesize cDNA from all the mRNA in a sample and then subjects the cDNA to PCR amplification using primers specific for the gene of interest.
Reverse Transcriptase Polymerase Chain Reaction )PT-PCR)
A technique used to detect the location of a specific mRNA using nucleic acid hybridization with a labeled probe in an intact organism.
In situ hybridization
A method to detect and measure the expression of thousands of genes at one time. Tiny amounts of a large number of single-stranded DNA fragments representing different genes are fixed to a glass slide and tested for hybridization with samples of labeled cDNA.
DNA Microarray Assays
A technique used to discover the function of a gene by cloning it, introducing specific changes into the cloned gene’s sequence, reinserting the mutated gene into a cell, and studying the phenotype of the mutant.
In vitro mutagenesis
A technique used to silence the expression of selected genes. RNAi uses synthetic double-stranded RNA molecules that match the sequence of a particular gene to trigger the breakdown of the gene’s messenger RNA.
RNA interference (RNAi)
Describing a cell that can give rise to all parts of the embryo and adult, as well as extraembryonic membranes in species that have them.
Totipotent
Describing a cell that can give rise to many, but not all, parts of an organism.
Pluripotent
Any relatively unspecialized cell that can produce, during a single division, one identical daughter cell and one more specialized daughter cell that can undergo further differentiation.
Stem Cell
A single base-pair site in a genome where nucleotide variation is found in at least 1% of the population.
Single Nucleotide Polymorphism (SNP)
A single nucleotide polymorphism (SNP) that exists in the restriction site for a particular enzyme, thus making the site unrecognizable by that enzyme and changing the lengths of the restriction fragments formed by digestion with that enzyme. A RFLP can be in condign or noncoding DNA.
Restriction Fragment Length Polymorphism (RFLP) “rif-lip:
Pertaining to an organism whose genome contains a gene introduced from another organism of the same or different species.
Transgenic Animal
An individual’s unique set of genetic markers, detected most often today by PCR or, previously, by electrophoresis and nucleic acid probes.
Genetic Profile
Simple sequence DNA containing multiple tenderly repeated units of two to five nucleotides. Variations in STEs act as genetic markers in STR analysis, used to prepare genetic profiles.
Short Tandem Repeats (STPs)
A plasmid of a tumor-inducing bacterium (the plant pathogen Agrobacterium) that integrates a segment of its DNA (T DNA) into a chromosome of a host plant. The ______ is frequently used as a vector for genetic engineering in plants.
Ti Plasmid
An organism that has acquired one or more genes by artificial means; also known as a transgenetic organism.
Genetically Modified (GM) Organisms
