3’ poly-A tail
a chain of adenine nucleotides added to the 3’ end of pre-mRNA during RNA processing
5’ methyl-G cap
a molecule added to the 5’ end of pre-mRNA during RNA processing
Activator Protein
a protein coded for by a regulatory gene that increases gene expression
Active Site
the part of an enzyme where the substrate binds
Active Transport
the movement of molecules across a semipermeable membrane requiring an energy input
ADP
adenosine diphosphate, the unloaded form of ATP
Affinity
the tendency of a molecule/atom to bind or react with another molecule/atom
Agarose Gel
a sponge-like gel used in gel electrophoresis that contains pores for DNA fragments to move through
Alpha Helix
an organised coiled secondary structure of proteins
Allosteric Site
a region on an enzyme that is not the active site
Alternative Splicing
the process where different exons may be spliced, resulting in a single gene producing multiple different mRNA strands
Aneuploidy
when a cell or organism varies in the usual amount of chromosomes in its genome by the addition or loss of a chromosome
Anneal
the joining of two molecules, for example two complementary DNA strands during the cooling phase of PCR
Antibiotic Resistance Gene
gene which confers antibiotic resistance
Anticodon
the sequence of three nucleotides on a tRNA molecule that recognises a specific sequence of three nucleotides (codon) on an mRNA strand
Antiparallel
a characteristic of DNA strands describing how each strand runs in an opposite direction to the other. One strand runs in a 3’ → 5’ direction and the other runs in a 5’ → 3’ direction
Anti-terminator Hairpin
a loop formed in mRNA when tryptophan is not present that ensures the transcription of the structural genes in the trp operon
Apoptosis
the controlled death of cells in the body. Also known as programmed cell death
Attenuator Sequence
part of the leader region within the trp operon that allows for attenuation
Band
a line seen in the gel after running gel electrophoresis that corresponds to a collection of DNA fragments of a specific size
Beta-Pleated Sheet
an organised folded secondary structure of proteins
Blunt End
the result of a straight cut across the double-stranded DNA by an endonuclease resulting in no overhanging nucleotides
Buffer
an ion-rich solution that carries electrical current through the agarose gel
Bulk Transport
a type of active transport that uses vesicles to move large molecules or groups of molecules into or out of the cell
catalyst
a substance capable of increasing the rate of a reaction without being used up
Chimeric
an organism or cell containing genetic material from another organism or cell
Chromosome
a structure made of protein and nucleic acids that carries genetic information
Cisgenic Organisms
a genetically modified organism that contains foreign genetic material from the same species
Coding Strand
d the strand of DNA not transcribed by RNA polymerase, contains an identical sequence to the mRNA strand produced
Codon
the sequence of three nucleotides in mRNA coding for one amino acid
Coenzyme
a non-protein organic cofactor that assists enzyme function. They release energy and are recycled during a reaction
Cofactor
any organic or inorganic molecule, such as a coenzyme or metal ion, that assists enzyme function
Collision Theory
An explanation of chemical reactions that states that in order to react molecules must hit one another
Competitive Inhibition
the hindrance of an enzyme by blocking the active site and preventing the substrate from binding
Complementary Base Pairing
describes which nucleotides can form hydrogen bonds with each other. C pairs with G, A pairs with T (or U in RNA)
Condensation Reaction
a reaction where two monomers join to form a larger molecule, producing water as a by-product
Conformational Change
a change in the three-dimensional shape of macromolecules such as proteins
CRISPR
short, clustered repeats of DNA found in prokaryotes which protects them against viral invasion
Cas-9
an endonuclease that creates a blunt end cut at a site specified by guide RNA
CRISPR-Cas9
a complex formed between gRNA and Cas9 which can cut a target sequence of DNA. Bacteria use this complex for protection from viruses and scientists have modified it to edit genomes
Denature
the disruption of a molecule’s structure by an external factor such as heat
DNA
a double-stranded nucleic acid chain made up of nucleotides. DNA carries the instructions for proteins which are required for cell and organism survival
Disulphide Bond
a strong covalent bond occurring between two sulphur atoms
Double Helix
the structure of double-stranded DNA in the nucleus of eukaryotic cells, where each DNA strand wraps around a central axis
DNA Profiling
the process of identification on the basis of an individual’s genetic information
Electrode
conductors of electricity that are attached to both ends of a gel allowing an electrical current to pass through
Electroporation
a method that involves delivering an electric shock to bacterial membranes to increase their membrane permeability and increase the likelihood of bacterial transformation
End Product Inhibition
a form of inhibition where the final product in a series of reactions inhibits an enzyme in an earlier reaction in the sequence
Endonuclease
an enzyme that breaks the phosphodiester bond between two nucleotides in a polynucleotide chain
Enzyme
an organic molecule, typically a protein, that catalyses (speeds up) specific reactions
Enzyme Inhibitor
a molecule that binds to and prevents an enzyme from functioning
Enzyme-Substrate Complex
the structure formed when an enzyme and substrate are bound together
Exocytosis
a type of bulk transport that moves large substances out of a cell
Exon
regions of DNA that code for proteins and are not spliced out during RNA processing
Forward Primer
regions of DNA that code for proteins and are not spliced out during RNA processing
Gel Electrophoresis
a technique that separates DNA fragments based on their molecular size
Gene
a section of DNA that carries the code to make a protein
Gene Knock-in
a technique in gene editing where scientists substitute or add nucleotides in a gene
Gene Knockout
a technique in gene editing where scientists prevent the expression of a target gene to understand its function in an organism
Gene Regulation
the control of gene expression, typically achieved by switching transcription on or off
Genetic Engineering
the process of using biotechnology to alter the genome of an organism, typically with the goal of conferring some desirable trait
Genetic Modification
the manipulation of an organism’s genetic material using biotechnology
Genetically Modified Organism
an organism with genetic material that has been altered using genetic engineering technology
Genome
the complete set of DNA housed within an organism
Heat Shock
a method that involves rapidly increasing and decreasing the temperature to increase membrane permeability in order to enhance the likelihood of bacterial transformation
Introns
non-coding regions of DNA that do not code for proteins. They are spliced out during RNA processing
Irreversible Inhibition
enzyme inhibition that involves stronger bonds that cannot be broken
Ligase
an enzyme that joins molecules, including DNA or RNA, together by catalysing the formation of phosphodiester bonds
Limiting Factor
a factor that prevents the rate of reaction from increasing
Limiting Reagent
a reactant that prevents the rate of reaction from increasing
Monomer
a molecule that is the smallest building block of a polymer
Non-Competitive Inhibition
the hindrance of an enzyme by binding to an allosteric site and changing the shape of the active site to prevent the substrate from binding
Nucleic Acid
the class of macromolecule that includes DNA and RNA. All nucleic acids are polymers made out of nucleotide monomers
Nucleotide
he monomer subunit of nucleic acids. Made up of a nitrogen-containing base, a five-carbon sugar molecule (ribose in RNA and deoxyribose in DNA), and a phosphate group
Optimal
the point at which for a given condition (e.g. temperature), the maximum function of an enzyme occurs.
Organic
a compound containing a carbon-hydrogen bond
Peptide Bond
the chemical bond linking two amino acids
Phenotype
the physical or biochemical characteristics of an organism that are the result of gene expression and the environment
Phosphodiester Bond
a strong covalent bond between nucleotides, linking a fivecarbon sugar to a phosphate group
Polypeptide
a long chain of amino acids. Proteins can be made of one or many polypeptides
Polymerase Chain Reaction
a laboratory technique used to produce many identical copies of DNA from a small initial sample
Polyploidy
when an organism contains additional sets of chromosomes in its genome
Primary Structure
the first level of protein structure, which refers to the sequence of amino acids in a polypeptide chain
Primer
a short, single strand of nucleic acids that acts as a starting point for polymerase enzymes to attach
Promoter
the sequence of DNA to which RNA polymerase binds
Protospacer
a short sequence of DNA extracted from a bacteriophage by Cas1 and Cas2, which has yet to be incorporated into the CRISPR gene
Protospacer Adjacent Motif (PAM)
a sequence of two-six nucleotides that is found immediately next to the DNA targeted by Cas9
Quaternary Structure
the level of protein structure where multiple polypeptide chains bond together, or other nonprotein groups are added to form a fully functional protein
R-Group
the variable portion of an amino acid molecule. It can be one of twenty variations and determines the identity of the amino acid
Random Coil
an irregular secondary structure of proteins that is neither an alpha helix nor a beta-pleated sheet
Rate
the speed at which a chemical reaction proceeds
Reading Frame
the order in which nucleotide triplets or codons are divided into a consecutive, non-overlapping sequence
Recognition Site
a specific target sequence of DNA upon which restriction endonucleases act
Recombinant Plasmid
a circular DNA vector that is ligated to incorporate a gene of interest
Regulatory Gene
a segment of DNA responsible for producing proteins that control the expression of other genes
Reporter Gene
A gene with an easily identifiable phenotype that can be used to identify whether a plasmid has taken up the gene of interest
Repressor Protein
a protein coded for by a regulatory gene that prevents gene expression by binding to its operator
Reverse Primer
a DNA primer that binds to the 3’ end of the coding strand and reads the DNA in the reverse direction to RNA polymerase
Reversible Inhibition
enzyme inhibition that involves weaker bonds that can be overcome
Ribosome
an organelle made of rRNA and protein that is the site of protein synthesis. Can be free in the cytosol or attached to the rough endoplasmic reticulum