Chapter 13 - Frontiers of Genetics Flashcards
recombinant DNA
used by scientists to combine genes from different organisms or species.
biotechnology
the use of organisms to perform tasks for humans
type - DNA technology
plasmids. why do scientists use them?
small circular DNA molecules found in bacteria that are separate from the much larger bacterial chromosome
use plasmids to move genes into bacteria
copies itself, resulting in gene sharing
restriction enzyme
“cuts” the DNA molecule into fragments at specific points
many developments in DNA technology came from ______ of the common bacterium, _________.
research
E. coli
steps of gene cloning?
- plasmid removed from cell
- desired gene is inserted into the plasmid
- becomes recombinant DNA (bc is combination of old and new DNA)
- recombinant plasmid put back in cell 4. replicates
restriction enzymes
the tools used to cut DNA (move to a new place)
protect bacteria against intruding DNA
- a restriction enzyme cuts the DNA into fragments. the pieces on the outside with no pairing are called ________. 2. a DNA fragment from another source is added. 3. the fragments stick together by _______. 4 . ________ pastes the fragments together.
- sticky ends
- base pairing
- DNA ligase
clones
identical copies of a desired gene produced by cell reproduction
genomic library?
what do scientists use to locate specific genes in the genomic library?
the complete collection of cloned DNA fragments from an organism.
nucleic acid probes
nucleic acid probe
a molecule that has been labeled with radioactivity (making it easy to detect)
- probe with single stranded DNA from clones
- probe tags to desired gene by binding to complementary sequence
GMO
Genetically Modified Organism
and organism that had acquired atleast one gene by artificial means
transgenic?
referred to if genetic material of GMO came from a different species
genetically modifying plants vs animals?
plants - insert a plasmid containing the desired gene into the plant cell
animal - desired gene placed into fertilized egg, which is placed in female body
PCR?
polymerase chain reaction -
a technique that makes identical copies of DNA molecules in large quantity and speed
(so DNA can be studied)
Gel Electrophoresis?
a technique for sorting DNA fragments by length.
SHORTER fragments pass MORE QUICKLY.
LONGER fragments pass SLOWLY.
Steps of copying DNA segments?
- heat added to separated strands of DNA
- cooled resulting in primers binding to strands
- DNA polymerase travels down the strands, adding nucleotides
- produces new cells (repeated)
genetic markers?
the banding pattern produced by specific portions of genome
stretches of DNA that vary from person to person
DNA fingerprint?
a unique, particular pattern of banding found on persons finger
control sequences
two short stretches of DNA that..
control clusters of genes
are found in prokaryotes
operon
cluster of genes with control sequences
promoter
one of the control sequences in an operon.
is a blinding site for an enzyme needed on DNA transcription
operator
second control sequence of operon.
acts like a switch - determines if RNA polymerase can attach to the promoter.
(switches promoter on and off)
repressor
a protein that turns the operator off by binding to it
enables prokaryotes to match their cell chemistry
gene expression
the transcription and translation of genes into proteins
transcription factors
promoter sequences that regulate proteins
controlled by chemical signals in the cell
Cellular Differentiation
a process where individual cells become more specialized in structure and function as the organism develops
stem cells
cells that remain able to differentiate into other types of cells
homeotic genes
master control genes that direct development of body parts in specific locations
