Unit 3 - chapter 4 Flashcards
(21 cards)
ch 4 - endonuclease
an enzyme that breaks the phosphodiester bond between two nucleotides in a nucleic acid chain
ch 4 - recognition site
a specific target sequence of DNA upon which restriction endonucleases act.
typically palindromic
ch 4 - restriction endonuclease
any enzyme that acts like molecular scissors to cut nucleic acid strands at specific recognition sites.
ch 4 - sticky end
the result of staggered cut through double-stranded DNA resulting in overhanging nucleotides.
ch 4 - blunt end
the result of a straight cut through double-stranded DNA resulting in no overhanging nucleotides.
ch 4 - overhanging nucleotides
unbonded nucleotides on the ends of double stranded DNA strands resulting form a staggered cut.
can bond to new nucleotides
ch 4 - ligase
an enzyme that joins together molecules, including DNA or RNA, by catalysing the formation of phosphodiester bonds.
ch 4 - polymerase
an enzyme that catalyses the synthesis of a polymer from monomers, such as forming a DNA strand from nucleic acids.
ch 4 - virus
non-cellular infectious agent composed of genetic material enclosed in a protein coat that requires a host organism to multiply - is not an organism.
ch 4 - bacteriophage
a virus that infects prokaryotic organisms.
ch 4 - CRISPR-Cas 9
A complex made up of Cas9 enzyme and guide RNA that can cut target sequences of DNA. Bacteria use it to defend against invading viruses, and scientists use it to edit genomes.
ch 4 - guide RNA
An RNA molecule made up of crisprRNA and tracrRNA that has a specific sequence determined by a bacterium’s CRISPR gene to guide Cas9 to a specific restriction site.
ch 4 - Cas9
An endonuclease that creates a blunt cut at a restriction site determined by gRNA.
ch 4 - CRISPR
short, clustered repeats of DNA found in prokaryotes that protect them from viral invasion.
ch 4 - spacer
a short sequence of DNA obtained from an invading bacteriophage that is added into the CRISPR array of a bacterium/prokaryote
ch 4 - PAM
A short sequence of nucleotides that is found immediately adjacent to the DNA targeted by Cas9, on the opposite strand.
ch 4 - gene therapy
the editing of a genome by scientists to repair genetic mutations by replacing defective genes with healthy ones.
ch 4 - sgRNA
single guide RNA is RNA created and used by scientists, made to instruct Cas9 to cut a specific gene when using CRISPR-Cas9 in gene editing.
ch 5 - gene knockout
a technique used in gene editing where scientists prevent the expression of a target gene to understand its function in an organism.
ch 4 - gene knock-in
a technique used in gene editing where scientists substitute or add nucleotides in a gene.
ch 4 - the polymerase chain reaction
a laboratory technique used to amplify a small initial sample of DNA.
