2024 Tus sau: Elizabeth Oswald | [email protected]. Kawg hloov kho: 2024-01-13 00:07
Li no, Permutation yog siv rau cov npe (kev txiav txim tseem ceeb) thiab Kev sib xyaw rau pawg (kev txiav txim tsis muaj teeb meem). Cov lus tso dag nto moo rau qhov sib txawv yog: "kev sib koom ua ke" yuav tsum tau hu ua "permutation lock". Qhov kev txiav txim koj muab tso rau hauv tus lej ntawm lub xauv tseem ceeb.
Dab tsi yog qhov sib txawv ntawm kev hloov pauv thiab kev sib xyaw ua ke?
permutations thiab kev sib xyaw ua ke, ntau txoj hauv kev uas cov khoom los ntawm cov txheej txheem tuaj yeem raug xaiv, feem ntau tsis hloov pauv, tsim cov subsets. Qhov kev xaiv ntawm subsets no yog hu ua permutation thaum qhov kev txiav txim ntawm kev xaiv yog qhov tseem ceeb, kev sib xyaw ua ke thaum kev txiav txim tsis yog qhov tseem ceeb.
Qhov twg muaj ntau qhov txiaj ntsig permutation lossis ua ke?
Nyob zoo, Muaj ntau qhov kev hloov pauv ntau dua li kev sib xyaw ua ke txij li kev hloov pauv tau txiav txim ua ke. Siv ib qho kev sib xyaw ua ke thiab kab lawv nyob rau hauv ntau txoj kev thiab peb muaj ntau qhov sib txawv. Hauv koj qhov piv txwv muaj 10C4=210 ua ke ntawm qhov loj 4 tab sis 4!
Koj paub thaum twg siv nCr lossis nPr?
nPr (permutations) yog siv thaum xaj teeb meem . Thaum qhov kev txiav txim tsis muaj teeb meem, koj siv nCr.
nCr txhais li cas hauv lej?
In lej, combination los yog nCr, yog txoj kev xaiv ntawm 'r' khoom los ntawm ib txheej ntawm 'n' khoom uas qhov kev txiav txim ntawm kev xaiv tsis muaj teeb meem. nCr=n!/[r!(n-r)!] Kawm ntxiv ntawm no: Kev sib xyaw.
Pom zoo:
Dab tsi yog qhov hloov pauv thiab hloov pauv hloov pauv?
Point mutations hloov ib leeg nucleotide. Frameshift kev hloov pauv yog ntxiv lossis tshem tawm ntawm nucleotides uas ua rau muaj kev hloov pauv hauv kev nyeem ntawv. frameshift thiab point mutation yog dab tsi? Ib qho kev hloov pauv cuam tshuam rau ib khub hauv paus.
Qhov kev hloov pauv no puas yuav ua rau muaj kev hloov pauv hloov pauv?
Yog li, yog tias muaj kev hloov pauv, piv txwv li, kev ntxig lossis tshem tawm ntawm nucleotide, tshwm sim, qhov no tuaj yeem ua rau kev hloov pauv ntawm kev nyeem ntawv. Nws hloov tag nrho cov amino acid ib ntus. Cov kev hloov pauv no yog hu ua frameshift mutation (tseem hu ua kev nyeem ntawv hloov pauv, nyeem ntawv hloov pauv, lossis framing yuam kev).
Qhov twg yog qhov kev hloov pauv hloov pauv hloov pauv?
Semiconservative replication piav qhia txog cov txheej txheem ntawm DNA replication nyob rau hauv tag nrho cov paub hlwb. DNA replication tshwm sim ntawm ntau lub hauv paus pib ntawm kev rov ua dua raws DNA qauv strand. Raws li DNA ob chav helix yog unwound by helicase, replication tshwm sim nyias ntawm txhua tus qauv strand nyob rau hauv antiparallel cov lus qhia.
Qhov kev hloov pauv twg yog xav tias yuav cuam tshuam los ntawm kev hloov pauv hloov pauv?
Dependent Variable Qhov sib txawv uas nyob ntawm lwm yam uas ntsuas. Cov kev hloov pauv no yuav tsum tau hloov pauv raws li qhov kev sim ua haujlwm ntawm tus kheej hloov pauv lossis hloov pauv. Nws yog cov nyhuv presumed. Qhov kev tshawb fawb hloov pauv twg yog qhov tshwm sim?
Los ntawm kev hloov pauv hloov pauv hloov pauv?
Kev hloov pauv hloov pauv hloov pauv (TMA) yog qhov isothermal (tsis hloov pauv nucleic acid kub), ib leeg-tube nucleic acid amplification system siv ob lub enzymes, RNA polymerase thiab thim rov qab kev sau ntawv. … Cov txheej txheem no tuaj yeem siv los tsom rau RNA thiab DNA.
