Unit 4 AOS 2: DNA manipulation Flashcards
Anneal
The joining together of DNA or RNA fragments by complementary base pairing
Bacterial transformation
The incorporation of DNA from another organism into a bacterial cell
Bacteriophage
A virus that infects bacteria
Blunt-end restriction enzyme
A restriction enzyme that leaves clean-cut ends because it cuts both strands of the DNA molecule at the same location within the recognition site
Complementary DNA (cDNA)
Double-stranded DNA that contains no introns; copied from mRNA by the enzyme reverse transcriptase
DNA amplification
The process of creating millions of identical copies of a DNA sample using the PCR reaction
DNA ladder
DNA standards; a set of DNA molecules of known size used as a ‘molecular ruler’ on gel electrophoresis to determine the size of other DNA molecules
DNA ligase
An enzyme that joins together fragments of DNA by forming a phosphodiester bond between the 3-hydroxyl and 5-phosphate of adjacent nucleotides
DNA polymerase
An enzyme that catalyses the formation of polymers of DNA by linking nucleotides into a chain by complementary base pairing with a template strand
DNA thermocycler
The machine used in the polymerase chain reaction (PCR) that alters the temperature in pre-programmed steps
Endonuclease
An enzyme, also called a restriction enzyme, that occurs naturally in bacteria and can cut DNA at a particular site (a recognition site); used in genetic engineering
Gel electrophoresis
A technique used for separating fragments of DNA, or different proteins, based on their molecular weight (or length). Fragments migrate through a gel at rates that are dependent on their length and charge
Gene cloning
The production of identical copies of a gene
Helicase
A type of enzyme that unwinds and unzips the two strands of a DNA molecule
Inducer
A molecule that regulates gene expression
lacZ gene
A gene in the lac operon that codes for beta-galactosidase; used in recombinant plasmids for detecting transformed bacteria
Ligase
An enzyme that joins together two molecules or fragments of molecules
Ligation
The process of joining two fragments of DNA using a DNA ligase enzyme
Microsatellite
A short repeated sequence of nucleotides found at a defined locus on a chromosome. The number of repeats varies between individuals and so are useful in DNA profiling
Plasmid
Small, circular pieces of double-stranded DNA found in bacterial cells. Plasmids replicate independently of the bacteria’s chromosomal DNA and are used in genetic engineering for creating recombinant DNA
Polymerase
A group of enzymes that catalyse the formation of polymers, in particular, the formation of nucleic acid polymers by complementary base pairing with a template strand
Polymerase chain reaction (PCR)
A laboratory technique used to amplify (make millions of copies of) a piece of DNA in a short period of time
Polymorphism
Genetic variation within a population. The least common allele has to have a frequency in a population of 1% or more to be considered polymorphism rather than mutation
Primer
A short strand of DNA or RNA that is able to bind or anneal to single-stranded DNA to create a region where DNA polymerase can join and initiate DNA synthesis
Recognition site
The short sequence of DNA bases recognised an cut by a restriction enzyme; also called a restriction site
Recombinant DNA
DNA that has been genetically engineered by joining fragments of DNA from two or more different organisms
Recombinant plasmid
A plasmid containing a foreign gene that has been inserted by the use of restriction enzymes and DNA ligase
Restriction enzyme
A type of enzyme also called an endonuclease, that occurs naturally in bacteria and can cut DNA at a particular site (a recognition site); used in genetic engineering
Reverse transcriptase
A type of polymerase enzyme used by retroviruses to copy their RNA genome into DNA; used in genetic engineering to copy messenger RNA (mRNA) into complementary DNA (CDNA)
RNA ligase
A ligase enzyme that joins together fragments of RNA
Sticky-end restriction enzyme
A type of restriction enzyme that makes a staggered cut in DNA to leave fragments with overhanging (or ‘sticky’) ends. The exposed bases of these sticky ends are then able to form complementary base pairs with nucleotides of other DNA molecules that have been cut with the same restriction enzyme
Taq polymerase
A type of heat-resistant DNA polymerase that is widely used in PCR
Thermophilic
Of or relating to an organism that favours high temperatures (a thermophile)
Transformed
A bacterium that has incorporated DNA from another organism into its own or taken up a plasmid containing foreign DNA
Gene expression
The expression of reading the information stored within a gene to create a functional product, typically a protein
Transformation
The process by which bacteria take up foreign DNA from their environment. Scientists use this process to introduce recombinant plasmids into bacteria
Vectors
An organism that is not affected by a disease but spreads it between hosts
Social Implications
Consequences that affect economics, politics or society
Biological implications
Consequences that affect ecosystems, environments or public health
Ethical Implications
Considerations based on moral or religious beliefs
Transgenic organism
A type of GMO that contains genetic material from another species that has been artificially introduced
GMOs
Genetically modified organism
An organism with genetic material that has been altered using gene engineering technology
Epidemic
A dramatically increased occurrence of a disease in a particular community at a particular time
Pandemic
An epidemic that has spread across multiple countries and/or continents
Cloning
To make a genetically identical organism or section of DNA
DNA profiling
The process of identification using genetic information. Also known as DNA fingerprinting
Rational drug design
A process in which scientists study the shape and charge of a target molecule and design a complementary-shaped drug that gives rise to a therapeutic benefit
