stem cell, epigentic, genetic modification and DNA Technology Flashcards
totipotent stem cell
limited time in embroyo
into any cell
pluripotent stem cell
- embroyo
-almost any
multipotent stem
- mammals
- few type
unipotent stem cell
- one type of cell
- mammals
induced pluripotent stem cell
pluripotent cell produces from unipotent celby trnscriptin factor
epigentic
heritable changes in gene function without changes to the base sequence of dna
What changes inhibiting transcription
- increase methylation
- deacrease in actelyation
increased methylation
- CH3 attaches to cytosine
- prevents the binding of transciption factors to the promoter sequence so the gene is not expressed
decreased actelyation
removal of COCH3 acteyal group becoming more condensed
- transcription is inhibiated as the genes are not accessible to transcription factors
benign tumour
- slower
- non-cancerous
- remain differntiated
- cell nucleaus is normal
malignant tumour
- faster
- cancerous
-undiffentinated - cell nucleus is larger and darker
hypermethylation
too much methylation
- tumour suppressor gene are not transcriped
- protein that slow down cell division are not produced
- uncontrolled cell division
hypomethylation
too little methylation of proto-oncogenes
- transciped coontinully
- increases production of protein stimulting cell division so uncontolled cell division
transgenic orgnisms
organisms has received transferred dna
making dna fragement by reverse transcriptase
- mRNA are isolated
mixed with free nucleotides and reverse transcriptase - using mRNA template to make cDNA joined togtehr by dna polymese to make a double strands
making dna fragements restriction endonuclease
-cuting dna at specific base sequence or recognition site
- restrcition endonuclese cuts produce sticky ends
sticky ends
dna o joined on to a different piece of dna
gene machine
- no mRNA starnd is required
transfermation by restriction endonuclease
- dna cut by restrcition endonuclease
- added promto and terminator
- enzyme RE cuts the plasmidd to allow sticky ends
- DNA ligase
- tanslated in to bacteria to recombined plasmid
promtor region
intiates transcription
terminator region
stops transcripion by inhibiting mRNA polymerase
identification of recmbined genes
gene marker
GEP gene produces green floursent protein
by UV light
identification of recmbined genes
gene marker
GEP gene produces green floursent protein
by UV light
PCR Steps
- heat at 95 to break H bond
- cool to allows the primer to joins nucielotide
- increase to 72 which is opptimum for dna polymerase
role of a primer
provide starting sequence for dna polymerase
prevents the dna from rejoinig
how dna fragment seperated
gel electrophersis
serperated according to size
transfered to nylon placed under x-ray
dna probes
short single strand that is complemantary to dna base sequence
- labelled to be identify
dna screening
- make dna probes
- use PCR to make copies
- extract by restriction endonuclease
- seperates by gel elctrohersis
- transfeed to nylon membrane
- dna probes is added
- washed
- identified by radioactivities
how to identify the relatness between people
- pcr to make copies of the smaple
- cut the restriction endonuclease
- seperates
- treated to form single strands
- transfered and viewed