Central Dogma & Recombinant Foundations
The flow of genetic information described by the Central Dogma of Molecular Biology.
What is DNA → mRNA → Protein?
This type of gene editing targets non-reproductive cells, ensuring that modifications affect only the individual patient and are not passed down.
What is somatic gene editing?
T4 DNA ligase catalyzes the formation of this covalent bond between adjacent 3'-hydroxyl and 5'-phosphate ends.
What is a phosphodiester bond?
Incubating bacterial cells on ice with these divalent cations neutralizes negative charges on the cell membrane and DNA prior to heat shock.
What are calcium ions (Ca2+)?
A standard PCR cycle relies on these three steps, in order, to amplify target DNA sequences.
What are Denaturation, Annealing, and Extension?
This organelle reads three-letter mRNA codons during translation and receives amino acids delivered by tRNAs.
What is the ribosome?
This targeted cancer therapy involves splicing a patient's T-cells to express receptors that target unique proteins on tumor cells.
What is CAR T-cell therapy?
An origin of replication, a selectable marker, and this dense cluster of restriction sites make up the core features of a cloning plasmid.
What is a Multiple Cloning Site (MCS)?
Enzymes like EcoRI leave these overhanging single-stranded ends that easily hydrogen-bond with complementary base sequences.
What are sticky (or cohesive) ends?
Isolated from a thermophilic bacterium, this enzyme synthesizes new DNA strands during the 72°C extension step of PCR.
What is Taq Polymerase?
This genetic element acts as the "on switch" in recombinant expression vectors to initiate transcription.
What is a promoter?
Cas9 will only bind and unwind target DNA if it detects this specific sequence directly adjacent to the target site.
What is a PAM (Protospacer Adjacent Motif) site?
In blue-white screening, successful gene insertion into the MCS causes this phenomenon, resulting in white colonies.
What is insertional inactivation (of the lacZ gene)?
One unit of restriction enzyme activity is defined as the amount required to completely digest this mass of template DNA in 1 hour.
What is 1 microgram (1μg)?
Nucleic acids migrate toward the positive electrode in gel electrophoresis because phosphate groups grant them this uniform chemical property.
What is a negative charge?
This universal feature of the genetic code allows bacterial ribosomes to read human mRNA templates identically to human ribosomes.
What is redundancy (or universality)?
Following a double-strand break, CRISPR utilizes this high-fidelity repair pathway along with a donor DNA template to achieve precise gene insertion.
What is Homology-Directed Repair (HDR)?
High glycerol concentrations, incorrect pH, or suboptimal salt levels can cause restriction enzymes to exhibit this unintended, non-specific cutting.
What is star activity?
Following heat shock, transformed cells are incubated in SOC/LB broth without antibiotics during this phase to express resistance proteins.
What is the recovery phase?
Home pregnancy tests and rapid viral assays commonly use this ELISA configuration where the target antigen is trapped between two antibodies.
What is a Sandwich ELISA?
Because prokaryotes lack organelles like the ER and Golgi apparatus, biomanufacturers use eukaryotic hosts to perform these necessary protein modifications.
What are post-translational modifications (PTMs)?
This bioethical dilemma balances using germline editing to prevent devastating conditions like Huntington's disease against using it for cosmetic or performance enhancements.
What is Therapy vs. Enhancement?
Scientists produced Humulin in E. coli by expressing chains A and B separately on different plasmids, then joining them together in vitro using this chemical bond.
What is a disulfide bond?
This physical transformation technique applies a high-voltage electrical pulse to temporarily open pores in the phospholipid bilayer.
What is electroporation?
In a Competitive ELISA, a patient sample containing a very high concentration of target antigen produces this level of signal output.
What is a weak (or zero/low) signal?