Chapter 20 Flashcards
(37 cards)
biotechnology
the manipulation of organisms or their components to make useful products
genetic engineering
the direct manipulation of genes for practical purposes
nucleic acid hybridization
key to many of the DNA techniques/tools (base pairing to complement = basis)
completed extinct genomes
wooly mammoth and neanderthals
DNA sequencing
a complete nucleotide sequence of a DNA molecule
1st based on dideoxy (chain termination sequencing)
dideoxy
the fragment of DNA is denatured to single strand and incubated with DNA ingredients
modified dNTPs added (fluorescent) -> added beginning 3’ until adding themselves
“Next-generation sequencing”
thousands of fragments sequenced in parallel
one nucleotide at a time
electronic monitors
How many nucleotides do women have?
approx 3 bill (completed using dideoxy)
What was a major thrust for the Human Genome Projeccr?
faster and cheaper sequencing
whole-genome shotgun approach
cloning and sequencing of fragments of randomly cut DNA followed by assembly into a single continuous sequence
map-based sequencing
recombination studies - overlapping DNA
DNA cloning
well-defined DNA segments in multiple identical copies
two types of cloning
gene cloning (the production of multiple copies of a single gene)
organismal cloning
Why clone just one gene?
agricultural improvements (pest-resistance)
environment (modify bacteria to clean)
medicine (like insulin)
plasmids
small circular DNA molecules that replicate separately from the bacterial chromosome
recombinant DNA
a molecule with DNA from two different sources
cloning vectors
area copied to create identical genes
Why are bacterial plasmids widely used as cloning vectors?
They are readily obtained, easily manipulated, easily introduced into bacterial cells, and once in the bacteria they multiply rapidly
Generally plasmid vector contains:
origin of replication
genes for antibiotic resistance
multiple cloning sites
restriction enzymes
cut DNA molecules at specific DNA sequences called restriction sites (making restriction fragments)
DNA ligase
an enzyme that seals the bonds between restriction fragments
polymerase chain reaction (PCR)
produce many copies of a specific target segment of DNA
transformation
inserting a new piece of DNA into bacteria
How will we know the bacteria took up the plasmid?
the antibiotic resistance gene (amp)