ch. 20 bio notes
electrical current
applied to the gel that causes negatively charged DNA to move through the gel from the cathode (-) to the anode (+)
DNA microarray assays
automation has allowed scientists to measure expression of thousands of genes at 1 time using _____*
applications of genetic engineering
basic research, applied research, development and production of treatments for human diseases (vaccines and drugs), and improved growth and disease resistance of agricultural plants and animals
nonrecombinant plasmid
blue colonies*
anneal
bond
transformation
process where a bacterium takes up a plasmid from the surrounding solution
restriction enzymes
proteins that are important tools for gene cloning and manipulation*
cloning
reproduction of the transformed bacterial cells results in _____ of the recombinant plasmid
intruding DNA
restrictio enzymes were discovered in bacteria, where they function to protect bacteria against intruding DNA from other organisms, such as bacteriophages
endonucleases
restriction enzymes are ____ that ut (hydrolyze) DNA moelcules at specific sequences, usually palindromic, called restriction sites
antibiotic resistance genes
allow for maintenance of the plasmid in bacterial host, usuallt the bacterium (E. coli-Escherichia coli)
DNA technology
allows us to study the sequence, expression, and function of a gene
genetic profile
an individuals unique DNA sequence characteristics; can be obtained by analysis of tissue or body fluids
restriction fragment length polymorphisms
(RFLPs); sequence changes that alter restriction sites*
RNA interference
(RNAi); gene expression can also be silenced using _____.
short tandem repeats
(STRs); varitations in the number of repeats of specific DNA sequences in a genome
denaturation
1st step in a PCR; high temperature is applied to melt the double-stranded DNA*
annealing
2nd step in a PCR; lower temperature incubation allows single-stranded complementary template DNAs and DNA primers to anneal*
extension
3rd step of a PCR; DNA polymerase catalyzes synthesis of new strands of DNA complementary to the DNA template*
cloning vector
plasmids used to clone genes
fluorescent dye
DNA is detected in a ____
compare patterns
DNA microarray assays ____ of gene expression in different tissues, at different times, or under different conditions*
bands
DNA molecules are resolved into ___ based on their size
agricultural productivity
DNA technology is being used to improve _____ and food quality and/or flavor.
shorter
The ___ the DNA molecule, the farther it moves.
-ACGT
The sticky end of the DNA restriction fragment -TGCA will pair with a DNA fragment with the sticky end ____.
bases of sticky ends
____ can hybridize (form base pairs) via hydrogen bonding with complementary bases ( A-T & G-C)
PCR and gel electrophoresis
_____ are used to aomplify and then identify STRs of different lengths
foreign DNA
a cloning vector is a DNA molecule that can carry _____ into a host cell and replicate within the host cell
probes
can be used to identify where or when a gene is transcribed in an organism
genetic engineering
can be used to modify the metabolism of microorganisms
genomic library
collection of recombinant vector clones produced by cloning DNA fragments from an entire genome*
blue
colonies of bacteria transformed with nonrecombinant plasmids containing intact lacZ genes will be ___ in color.
white
colonies of bacteria transformed with recombinant plasmids with disrupted lacZ genes will be ___, since they do not produce functional B-galactosidase
cDNA
complementary DNA; made by cloning DNA made *
X-gal
compound used to identify colonies produed by bacteria transformed with recombinant, lacZ disrupted plasmids.
restriction fragment analysis
detects DNA differences that affect restriction sites*
DNA ligase
enzyme that forms covalent bonds between restriction fragments
restriction enzymes
enzymes isolated from bacteria that recognize specific sequences in DNA and then cut the DNA to produce fragments call restriction fragments
PCR
polymerase chain reaction*
single gene defects
gene therapy is likely to be most successful with diseases caused by_____
Template DNA
in PCR; contains the taret DNA sequence to be amplified*
Thermostable DNA polymerase
in PCR; heat-tolerant DNA strands
buffered solution
in PCR; provides a suitable, pH stabilized chemical environment required for optimum activity and stability of the DNA polymerase*
primers
in PCR; short, synthetic, single-stranded DNAs that bind to the ends of the DNA sequence being amplified*
recombinant DNA
in _____ , nucleotide sequences from 2 different sources (often consisting of sequences from 2+ different species)are combined in vitro into the same DNA molecule.
recombinant plasmid
in gene cloning _____ is introduced into a bacterial cell by a process called transformation
in vitro reaction
in gene cloning, DNA from an organism of interest is inserted into a plasmid, usually using an _______
lacZ gene
in many cloning vectors, the cloning site is contained in the bacterial ____
same restriction enzyme
in order to insert a human gene into a plasmid, both must be cut by the ________; doing so will result in the formation of complementary sticky ends
anode
positively charged
high spealized cells
like muscle cells or neurons, only express a tiny fraction of their genes
transgenic organisms
made by introducing genes from 1 organism into the genome of another organism
biofuels
make use of crops such as corn and soybeans to replace fossil fuels
transgenic animals
may be created to exploit attributes provided by genes from other organisms, such as genes for faster growth or larger muscles
genetic engineering
modification of characteristics of an organism by manipulating its genetic material
bacteria and their plasmids
most methods for cloning DNA in the laboratory share general features, like the use of ______
MCS
multiple cloning site; has restriction enzyme cut sites
cathode
negative charged
cloning
occurs with the replication of a recombinant plasmid; making of identical copies
cloning and manipulation
of genes involves the use of recombinant DNA technologies
agarose gel electrophoresis
one method of rapidly analyzing and compairing DNA samples*
determine gene function
one way to _____ is to disable the gene and observe the consequences.
in vitro
outside a living organism (as in a test tube)
plasmid
small circular DNA molecule obtained from a bacterium; serves as a cloning vector
molecular sieve
technique uses an agarose gel as a ______ to separate DNA molecules by size
B-galactosidase
the lacZ gene encodes the enzyme _____
biotechnology
the manipulation of organisms or heir genetic components to make useful products
sticky ends
the unpaired nucleotides produced by the action of restriction enzymes; called sticky ends since theyll stick to a complementary single-stranded sequence
DNA cloning
to work directly with specific genes, scientists must prepare large quantities of gene-sized fragments of DNA in identical copies
cloned genes
useful for making many copies of a particular gene and for producing gene products (protein or RNA)
in situ hybridization
uses fluorescent dyes attached to oligonucleotide probes to identify the location of specific mRNAs in cell tissues or even intact organisms*
in vitro mutagenesis
using ______, mutations are introduced into a cloned gene, thereby altering or destroying its function
polymorphisms
variations in DNA sequence
mutants phenotype
when mutated gene is returned to the cell, the normal genes function might be determined by examining the _____
recombinant plasmid
white colonies*
in vivo
within a living organism (opposite of in vitro)
blue pigmented
x-gal is hydrolyzed by the lacZ gene product, B-galactosidase, to yeild a _____ product.