tulun.....!!!

ermmm,sape ade maklumat pasal kebaikan n keburukan PCR(polymerase chain reaction)..
org kna siapkan asignment,tp xjumpe r lam tenet sal benda ni.huhu

1) The High Sensitivity of PCR
Due to the extremely high sensitivity of PCR, contamination from non-template PCR present in the lab environment (from bacteria,viruses, and your own DNA) presents a real problem. Precautions therefore must be taken. Several steps can be taken to prevent and minimize PCR contamination including the use of aerosol barrier tip filters, laminar flow cabinet, and a special preparation area for PCR separate from the DNA isolation area.

2) Polymerase Errors
DNA polymerase are not perfect by any means, however they are quite good at what they do. Mistakes and errors do happen in PCR by DNA polymerases in the test tube and in the human body. The polymerases
used in PCR often lack 3' to 5' exonuclease activity such as Taq polymerase. This enzyme lacks the ability to correct misincorporated nucleotides, an activity which is present in higher eukaryotes. A polymerase lacking the 3' to 5' exonuclease activity has a higher error rate, around 1 in 10000 bases are misincorporated.
Recombinant polymerases have been generated and other polymerases have been isolated which are available to more accurate PCR and have a variety of applications such as sequencing. Examples of polymerases with 3' to 5' exonuclease activity include: Vent, which is extracted from Thermococcus litoralis , Pfu which is extracted from Pyrococcus furiosus, and Pwo which is extracted from Pyrococcus woesii .

3) PCR Polymerase Enzyme Proficiency and PCR Product Size / Length Limitations

DNA polymerase are proficient enough to efficiently amplify DNA products up to a few thousand basepairs (2-5 kb). PCRs of longer products are less efficient due to enzyme activity loss, and
inaccuracies introduced by longer PCRs. Adding fresh DNA polymerase helps with enzyme activity lost due to the half life of the polymerase, however this does not help when accurate PCR is required.

It is possible to amplify PCR products up to 20kb using lower or slower heating cycles and special mixtures of polymerases. Long and Accurate PCR is accomplished by using mixtures of processive polymerases and high fidelity Polymerases. (http://www.pcrstation.com/pcr-limitations/)

4) Highly trained staff are required
5) High cost for to nucleotide mix comercially prepared for dna replication

Yang lain x ingat...

Cuba check kat libary mesti banyak...

tornado,sy kt umah skgni..jd ssh nk cr bnda cm2 kt library cni.
ermm,pedang,thanx byk2 ...

nur ana wrote:tornado,sy kt umah skgni..jd ssh nk cr bnda cm2 kt library cni.
ermm,pedang,thanx byk2 ...

alah abg tornado tak kisah kan. dia boleh gi hantar kat rumah (kalau pakai jerung letak kat rumah je buat ape) kihkihkih.

Developed in 1983 by Kary Mullis, PCR is now a common and often indispensable technique used in medical and biological research labs for a variety of applications. These include DNA cloning for sequencing, DNA-based phylogeny, or functional analysis of genes; the diagnosis of hereditary diseases; the identification of genetic fingerprints (used in forensics and paternity testing); and the detection and diagnosis of infectious diseases. In 1993 Mullis won the Nobel Prize in Chemistry for his work on PCR.

thanx intang 4 ur info..

wa....banyaknye jawapan...ni gamba tudung ijau nie....macam baru 1st year je...kalau nak banyak jawapan..pi VIROLOGI HKL..jumpa anak2 buah Dr MANGALAM....Dr MANGALAM dah pencen....atau pi jumpa Dr MANGALAM kat umah die...susah2 sangat..tapi je perkataan penuh PCR tu..cari dalam wikipedia....mesti ada...
1 http://en.wikipedia.org/wiki/Polymerase_chain_reaction
2 http://books.google.com.my/books?hl=en&id=tl-VuLDM_TUC&dq=PCR&printsec=frontcover&source=web&ots=u_o-cKNAgZ&sig=8INCvLNVbKqXucIdbHhpQWThS3g&sa=X&oi=book_result&resnum=2&ct=result
3 http://users.ugent.be/~avierstr/principles/pcr.html
dan banyak lagi...

inilah antara nota2 yang boleh digunapakai...

tereerrrrrr..................

thanx pacimot...thanx byk2.mmg bguna sgt info yg awk bg 2..n abg ananz,hehe...long time no c ya..

Gambar rajah PCR boleh didapati di link seperti berikut:


http://images.google.com.my/images?client=firefox-a&rls=org.mozilla%3Aen-US%3Aofficial&hl=en&q=polymerase+chain+reaction&btnG=Search+Images&gbv=2

sy dh bjy siapkn asgnment..thanx pd sume yg sudi bg mklumat serba sdikit..xcikit,mmg byk sbnrny..thanx

ade sesape yg bole huraikan dalam bahasa ringkas bahasa ibunda?takut nt adik nur ana kite ni tesalah translate je.adik nur ana jgn tau amik copy paste je,try tanye abg2 ng kakak2 ni skali,dorang phm ke idok bebenornye.hahaahha..
sebab dah bejaye buat asgmnt tu,meh sini abg blanje piza capati..

piza capati????
ade eh?
nk nk nk!!!

bkn xpandai bhs ingris.muet dulu ni dpt band 4 tau.bkn nk ekyen.pnh amik muet kan?bkn ke care tebaik nk mudah ingat kite ubah blk ayat tu gune bhase yg kite mudah phm.buat camtu lgla sng nk ingat.menghafal dengan memahamkan dua istilah belainan.

emm..sblm masuk mlt,pnh masuk klas blaja bahase jepun ng mandarin.sikit byk tu bolela nk phm skit..bhs ingrs tu da bole kire bhs kedua da.time skola ade blaja bhs arab.tapi time tu tergolong dalam budak2 jahat..time kelas bhs arab pakat lari taknak masuk kelas.kalo tak skg ahlan wasahlan,kaifahaluka?? naam,ana bikhoir...da bole jd ustaz 3D da...

ana..jom.kite g mkn piza capati.kat medan tu pun ade gak.tapi plg best nasi ayam madu die..pergghh...meleleh air liur bile tringat..

kt medan ade gk ker mknn yg bley wt air liur mleleh?
xku sangka...

ade ana..nk2 time pose camni.haha.i know wut u did last pose...