kk2 glossary
Term | Definition | Example/image (if applicable) |
agarose gel | a special type of porous gel used in gel electrophoresis, which allows for DNA to be separated by fragment size | |
annealing | the second stage in PCR, in which primers attach to the single-stranded DNA | |
bacterial transformation | process in which bacterial cells take up segments of foreign DNA that become part of their genetic make-up | |
blunt ends | ends of a DNA fragment with no overhanging bases after being cut by an endonuclease | |
complementary DNA (cDNA) | a strand of DNA that has complementary bases to the opposite strand and is usually produced through reverse transcription | |
CRISPR-Cas9 | a tool for precise and targeted genome editing that uses specific RNA sequences to guide an endonuclease, Cas9, to cut DNA at the required positions | |
denaturing | the first stage in PCR, in which a double-stranded piece of DNA is heated and separated into single-stranded DNA | |
DNA fingerprinting | technique for identifying DNA from different individuals based on variable numbers of tandem repeats of short DNA segments near the ends of chromosomes | |
DNA profiling | technique for identifying DNA from different individuals based on variable regions known as short tandem repeats (STRs) or microsatellites | |
DNA sequencing | identification of the order or sequence of bases along a DNA strand | |
electroporation | a technique that uses brief exposure of host cells to an electric field to enable the entry of segments of foreign DNA into the cells | |
endonucleases | enzymes, also known as restriction enzymes, that cut at specific sites within DNA molecules | |
ethidium bromide | a dye that binds to DNA and illuminates under UV light | |
extension | the third stage in PCR, in which the Taq polymerase enzyme synthesises a new strand of DNA by adding free nucleotides | |
gel electrophoresis | a technique for sorting a mixture of DNA fragments (and other molecules with a net charge) through an electric field on the basis of different fragment lengths | |
genetically modified organisms (GMOs) | organisms whose genomes are altered through the use of genetic engineering technology | |
genome editing | a process by which changes are made to the nucleic acid sequence of genes; also termed gene editing | |
heat shock | a technique to transform bacteria in which cells are suspended in a ice cold solution and then moved into a warm solution to increase plasma membrane fluidity | |
hypervariable regions | regions in DNA that are highly polymorphic | |
insulin | a hormone that allows for glucose to enter cells, reducing blood glucose levels | |
ligase | an enzyme that catalyses the joining of two double-stranded DNA fragments | |
origin of replication (ORI) | a DNA base sequence in a plasmid in which DNA replication begins | |
plasmid | a small circular piece of double-stranded DNA that is able to reproduce independently and may be taken up by cells (usually bacteria) in addition to chromosomal DNA | |
polymerase | enzyme involved in synthesising nucleic acids | |
polymerase chain reaction | a technique used to amplify a segment of DNA | |
recombinant plasmids | plasmids that carry foreign DNA | |
restriction enzyme | enzymes, also known as endonucleases, that cut at specific sites within DNA molecules | |
reverse transcriptase | enzyme that directs the formation of copy DNA from a messenger RNA template through reverse transcription | |
selectable marker | genes carried by plasmids for certain traits, often for antibiotic resistance | |
short tandem repeats (STRs) | chromosomal sites where many copies of a short DNA sequence are joined end-to-end; the number of repeats is variable between unrelated people | |
sticky ends | ends of a DNA fragment with overhanging bases after being cut by an endonuclease | |
Taq polymerase | an enzyme used in PCR that adds free nucleotides to the single stranded DNA in order to synthesise a new strand | |
transgenic organisms | organisms that carry in their genomes one or more genes artificially introduced from another species | |
vector | an agent or vehicle used to transfer pathogens or genes between cells and organisms | |
probe | single-stranded segment of DNA (or RNA) carrying a radioactive or fluorescent label with a base sequence complementary to that in a target strand of DNA |