Cov kev zoo sib thooj ntawm DNA thiab RNA. Comparative yam ntxwv ntawm DNA thiab RNA: rooj

Txhua nyob kab mob nyob rau hauv lub ntiaj teb no tsis zoo li lwm tus. Lawv txawv los ntawm txhua lwm yam tsis tau tsuas yog los ntawm cov neeg. Tsiaj txhu thiab cov nroj tsuag ntawm ib hom kuj muaj sib txawv. Yog vim li cas rau qhov no yog tsis tau tsuas yog qhov sib txawv nyob tej yam kev mob thiab lub neej yaam puab paub. Lub kheej ntawm txhua tus kab mob yog pw nyob rau ntawd los ntawm caj khoom.

Tseem ceeb thiab nthuav cov lus nug txog cov nucleic acids

Txawm tias ua ntej yug me nyuam ntawm txhua kab nws muaj nws tus kheej txheej ntawm cov noob uas yuav txiav txim kiag li tag nrho cov nta ntawm cov qauv. Nws tsis yog tsuas yog lub tsho tiv no xim los yog nplooj zoo, piv txwv li. Lub noob raug nteg thiab tseem ceeb tshaj yam ntxwv. Tom qab tag nrho, miv tsis tau yug ib tug hamster, ib tug nplej noob yuav tsis loj hlob baobab.

Thiab rau tag nrho cov no loj heev npaum li cas ntawm cov ntaub ntawv raws li cov nucleic acids - DNA thiab RNA molecules. Lawv tseem ceeb yog ib qhov nyuaj rau overestimate. Tom qab tag nrho, lawv tsis tau tsuas yog khaws ntaub ntawv thoob plaws hauv lawv lub neej, lawv yuav pab kom siv nws nrog kev pab los ntawm cov nqaijrog, thiab nyob rau hauv tas li ntawd, kis mus rau cov tiam tom ntej. Yuav ua li cas lawv ua, nyuaj npaum li cas muaj cov qauv ntawm DNA thiab RNA? Yuav ua li cas lawv zoo li cas thiab dab tsi yog qhov txawv? Nyob rau hauv tag nrho cov no peb yuav to taub nyob rau hauv cov nram qab no ntawm daim ntawv no.

Tag nrho cov ntaub ntawv peb yuav soj ntsuam nyob rau hauv qhov chaw, pib nrog cov qauv rau kev. Ua ntej, peb paub txog hais tias xws li nucleic acids, lawv twb qhib, ces tham txog lawv cov qauv thiab kev khiav dej num. Thaum lub kawg ntawm tsab xov xwm peb tseem tos ib tug sib piv cov lus ntawm RNA thiab DNA, uas koj muaj peev xwm thov tau txhua lub sij hawm.

Yuav ua li cas yog ib tug nucleic acid

Nucleic acid - yog organic tebchaw muaj ib tug siab molecular luj, yog polymers. Nyob rau hauv 1869 lawv twb xub piav Fridrihom Misherom - biochemist los ntawm Switzerland. Nws qhia tau tshuaj muaj li ntawm phosphorus thiab nitrogen los ntawm kua paug hlwb. Piv txwv tias yog tias nws yog xwb nyob rau hauv lub nuclei, ib tus paub txog hu nws nukleina. Tab sis qhov uas tom qab qhov kev sib cais ntawm cov nqaijrog, nws tau raug hu ua nucleic acid.

Nws monomers yog nucleotides. Lawv tus nqi nyob rau hauv lub acid molecule zuj zus rau txhua hom. Nucleotides yog molecules muaj li ntawm peb qhov chaw:

• monosaccharide (pentose), yuav ua tau ntawm ob hom - ribose thiab deoxyribose;
• nitrogenous puag (ib qho ntawm plaub);
• phosphoric acid residue.

Tom ntej no peb saib qhov sib txawv thiab zoo sib xws ntawm DNA thiab RNA, lub rooj ntawm qhov kawg ntawm tsab xov xwm yuav sum txog cov tag nrho.

Nta ntawm cov qauv: pentose

Tus thawj tshaj plaws kev zoo sib thooj ntawm DNA thiab RNA yog hais tias lawv muaj monosaccharides. Tab sis lawv yog cov sib txawv rau txhua tus acid. Uas yog, nyob ntawm seb ib tug pentose molecule, nucleic acid, muab faib los ntawm cov DNA thiab RNA. Tus qauv ntawm DNA yog muaj deoxyribose, raws li nyob rau hauv RNA - ribose. Ob pentose acids pom nyob rau hauv xwb nyob rau hauv β-daim ntawv.

Nyob rau hauv deoxyribose lub thib ob carbon atom (xws li 2 ') yog tsis tuaj kawm ntawv oxygen. Zaum hais tias nws tsis tuaj kawm ntawv:

• shortens lub daim ntawv cog lus ntawm C ₂ thiab C _3;
• Nws yog ua ib tug DNA molecule ruaj khov;
• Nws tsim tej yam kev mob rau compact packing ntawm DNA nyob rau hauv lub nucleus.

Kev sib piv ntawm cov lug: nitrogenous bases

Comparative yam ntxwv ntawm DNA thiab RNA - yog tsis yooj yim. Tab sis qhov sib txawv yuav pom los ntawm heev thaum pib. Nitrogenous bases - nws yog ib lub tseem ceeb tshaj plaws "lub tsev blocks" nyob rau hauv peb molecules. Lawv nqa tshuaj ntsuam genetic ntaub ntawv. Ntau precisely, tsis yog lub hauv paus, thiab lawv txiav txim nyob rau hauv cov saw hlau. Lawv yog cov purine thiab pyrimidine.

Muaj pes tsawg leeg ntawm DNA thiab RNA monomers txawv twb theem: nyob rau hauv deoxyribonucleic acid peb ua tau raws li adenine, guanine, cytosine thiab thymine. Tab sis es tsis txhob ntawm thymine nyob rau hauv RNA muaj uracil.

Cov tsib bases yog thawj (loj), lawv tshwm sim tawm lub feem ntau ntawm cov nucleic acids. Tab sis sib nrug ntawm no, tseem muaj lwm leej lwm tus. Qhov no tshwm sim heev tsis tshua muaj, yog cov neeg me los luj. Thiab nkawd ob leeg nyob rau hauv ob qho tib si acids - qhov no yog lwm kev zoo sib thooj ntawm DNA thiab RNA.

Cov kab sab ntawm lub nitrogenous bases (thiab correspondingly nucleotides) nyob rau hauv lub DNA saw sij uas cov nqaijrog yuav coj los ua ke no cell. Uas molecules yog tsim thaum lub caij nyob rau hauv lub cev cov kev xav tau.

Cia peb tig mus rau theem ntawm lub koom haum ntawm nucleic acids. Yuav kom comparative cov yam ntxwv ntawm DNA thiab RNA tau tshaj kom tiav thiab lub hom phiaj, peb yuav saib cov qauv ntawm txhua. Nyob rau hauv lub DNA ntawm plaub, thiab tus naj npawb ntawm theem ntawm lub koom haum nyob rau hauv RNA nyob ntawm nws hom.

Tus foundations ntawm DNA qauv, qauv hauv paus ntsiab lus

Tag nrho cov muaj tus kab mob yog muab faib ua prokaryotes thiab eukaryotes. Qhov no kev faib yog raws li nyob rau hauv cov tub ntxhais tsim. Cov thiab lwm yam DNA pom nyob rau hauv lub cell nyob rau hauv daim ntawv ntawm cov chromosomes. Qhov no tshwj xeeb tsa nyob rau hauv uas lub deoxyribonucleic acid molecule ua txhua yam rau proteins. DNA muaj plaub theem ntawm lub koom haum.

Lub hom qauv yog sawv cev los ntawm ib cov saw ntawm nucleotides, ib theem zuj zus uas yog nruj me ntsis cai rau txhua kab thiab uas yog interconnected phosphodiester bonds. Lossis loj strides nyob rau hauv txoj kev tshawb no ntawm cov qauv ntawm cov DNA saw mus txog Chargaff thiab nws neeg ua hauj lwm. Lawv nrhiav tau tias tus piv ntawm cov nitrogenous bases yog raug rau tej kev cai.

Lawv hu ua Chargaff cov kev cai. Tus thawj ntawm cov xeev hais tias tus nqi ntawm purine bases yuav tsum sib npaug zos rau cov nqi ntawm pyrimidine. Nws yuav ua kom meej tom qab nyeem ntawv cov theem nrab qauv ntawm DNA. Vim hais tias ntawm nws cov nta yuav tsum lub thib ob txoj cai: lub hniav puas piv A / T thiab T / C sib npaug zos rau kev sib sau. Cov tib txoj cai tuas muaj tseeb rau lub thib ob nucleic acids - hais tias ib lub zoo sib thooj ntawm DNA thiab RNA. Tsuas yog nyob rau ob qhov chaw ntawm thymine yeej ib txwm muaj nqis uracil.

Tsis tas li ntawd, muaj ntau zaum pib faib cov DNA ntawm ntau hom tshaj ib tug loj tus naj npawb ntawm thaj av. Yog hais tias tus lej "A + T" ntau "D + C", xws DNA yog hu ua tus saib-hom. Yog hais tias nyob rau hauv tsis tooj, peb yuav soj ntsuam nrog lub GC-hom DNA.

theem nrab qauv qauv twb npaj siab nyob rau hauv 1953 los ntawm zaum Watson thiab Crick, thiab nws tseem yog zoo li no. Tus qauv yog ib tug muab ob npaug rau helix, uas muaj ob antiparallel strands. Lub ntsiab yam ntxwv ntawm lub qhov qauv yog:

• muaj pes tsawg leeg ntawm txhua DNA strand yog nruj me ntsis kev rau lub hom;
• hydrogen daim ntawv cog lus nruab nrab ntawm cov saw hlau, yog tsim nyob rau hauv lub hauv paus ntawm complementarity ntawm nitrogenous bases;
• polynucleotide chains entwine txhua lwm yam, txoj kev pravozakruchennuyu kauv, uas yog hu ua "Helix";
• residues ntawm phosphoric acid nyob sab nraum muab kauv nitrogenous bases - sab hauv.

Ntxiv mus, denser, nyuaj

Lub tertiary qauv ntawm DNA - yog superspiralizirovannaya qauv. Uas yog, Ntxiv, uas nyob rau hauv lub molecule lub ob chains yog cov nrog txhua lwm yam, rau cov zoo dua compactness ntawm DNA yog lub qhov txhab nyob rau hauv tshwj xeeb cov nqaijrog - histones. Lawv muab faib ua tsib chav kawm raws li cov ntsiab lus ntawm lysine thiab arginine.

Qhov tseeb theem ntawm DNA - chromosome. Mus saib yuav ua li cas zoo nws yog stacked cab kuj ntawm caj ces, xav txog cov nram no: yog hais tias tus Eiffel Tower mus los ntawm tag nrho cov theem ntawm compaction, raws li zoo raws li DNA, nws yuav tsum muab tso rau hauv ib tug matchbox.

Chromosomes yog ib (chromatids muaj ib qho) thiab ob (muaj li ntawm ob chromatids). Lawv muab txhim khu kev qha cia ntawm caj ces, thiab muaj peev xwm tig ib ncig thiab qhib nkag tau mus rau cov yam qhov chaw, yog tias tsim nyog.

Hom ntawm RNA yam ntxwv nta

Sib nrug los ntawm qhov tseeb hais tias tej RNA yog txawv los ntawm lub DNA ntawm nws cov thawj qauv (hauv lub qhaj ntawv ntawm thymine, lub xub ntiag ntawm uracil), lub koom haum nram qab no kuj txawv muaj ntau seem:

1. Thauj RNA (tRNA) yog ib tug hluas-tso tseg molecule. Yuav kom ua tau lawv muaj nuj nqi ntawm thauj amino acids mus rau lub site ntawm protein synthesis, nws muaj ib tug heev txawv txawv theem nrab qauv. Nws yog hu ua "clover nplooj". Txhua lub voj nws ua nws txoj kev ua, tab sis cov tseem ceeb tshaj plaws yog cov acceptor qia (nws clings mus rau ib qho amino acid) thiab anticodon (uas yuav tsum tau coincide nrog lub codon rau tus tub txib RNA). Lub tertiary qauv ntawm tRNA kawm ib me ntsis, vim hais tias nws yog heev yooj yim mus hais tias ib tug qauv tsis rhuav lub theem siab ntawm lub koom haum. Tab sis ib co ntawm cov ntaub ntawv tus zaum muaj. Piv txwv li, nyob rau hauv poov hloov lwm lub tsev RNA yog nyob rau hauv daim ntawv ntawm daim ntawv L.
2. Cov tub txib RNA (kuj raug xa mus rau raws li cov lus qhia) ua cov kev ua ntawm cov ntaub ntawv hloov lwm lub tsev ntawm DNA mus rau lub site ntawm protein synthesis. Nws yuav qhia dab tsi txog cov protein yuav nws thiaj li tsiv mus nyob rau nws nyob rau hauv ribosome synthesis. Nws thawj qauv - ib-tso tseg molecule. Secondary qauv yog heev tham, nws yog tsim nyog los txiav txim raug thaum pib ntawm lub protein synthesis. mRNA tsim nyob rau hauv daim ntawv ntawm cov pins, uas yog nyob rau hauv lub xaus ntawm seem ntawm qhov pib thiab thaum xaus ua ntawm cov protein.
3. Ribosomal RNA muaj nyob rau hauv lub ribosomes. Cov organelles yog muaj li ntawm ob subunits, txhua tus uas yog nyob rau ntawm qhov chaw rRNA. Qhov no nucleic acid thiab txiav txim seb qhov kev tso kawm ntawm tag nrho cov ribosomal cov nqaijrog thiab haumxeeb chaw zov me nyuam no organelle. RRNA thawj qauv yog sawv cev los ntawm ib tug nucleotide ib theem zuj zus raws li nyob rau hauv lub yav dhau los versions acid. Nws yog lub npe hu hais tias cov theem kawg yog pw rRNA pos kawg feem ntawm ib tug saw. Cov tsim ntawm cov petioles ntxiv muaj txhawb mus rau lub compaction ntawm tag nrho cov qauv.

DNA zog

Deoxyribonucleic acid ua raws li ib tug repository ntawm kev tshuaj ntsuam genetic ntaub ntawv. Nws yog nyob rau hauv nws cov nucleotide ib theem zuj zus "thaum" tag nrho cov nqaijrog nyob rau hauv peb lub cev. Cov DNA lawv tsis tau tsuas yog khaws cia, tab sis kuj zoo-kev tiv thaiv. Thiab txawm hais tias ib qho yuam kev tshwm sim thaum luam, nws yuav raug kho. Yog li, tag nrho cov kev tshuaj ntsuam genetic khoom nyob twj ywm thiab nce mus txog progeny.

Nyob rau hauv thiaj li yuav qhia cov lus qhia rau xeeb leej xeeb ntxwv, cov DNA muaj lub peev xwm mus ob npaug. Qhov no yog hu ua replication. Comparative rooj ntawm RNA thiab DNA yuav qhia rau peb hais tias ib lub nucleic acid yog tsis muaj peev xwm ua tau li ntawd. Tiam sis nws muaj ntau ntau lwm yam kev khiav dej num.

RNA zog

Txhua yam ntawm RNA ua nws zog:

1. Hloov ribonucleic acid muab cov amino acid me nyuam mus rau ribosomes, qhov twg proteins uas ua. tRNA theem tsis tau tsuas yog ib lub tsev ntaub, nws kuj yog muab kev koom tes nyob rau hauv lub Vocabulary ntawm lub codon. Thiab los ntawm nws txoj hauj lwm nyob rau yuav ua li cas lub protein yuav tau ua kom raug.
2. Cov tub txib RNA nyeem ntaub ntawv los ntawm DNA thiab kev hloov tsheb mus rau ntawm qhov chaw uas muaj protein ntau synthesis. Nws muaj nws yog txuas mus rau lub ribosome thiab dictates qhov kev txiav txim ntawm cov amino acids nyob rau hauv lub protein.
3. Ribosomal RNA muab kev ncaj ncees organelle qauv, regulates lub lag luam ntawm tag nrho cov kev haumxeeb chaw zov me nyuam.

Qhov ntawd yog lwm kev zoo sib thooj ntawm DNA thiab RNA: nkawd ob leeg saib xyuas ntawm lub caj ntaub ntawv nqa los ntawm ib tug cell.

Kev sib piv ntawm DNA thiab RNA

Yuav kom npaj tag nrho cov saum toj no, peb yuav sau nws nyob rau hauv tag nrho cov rooj.

Yog li ntawd, peb hais lus luv luv txog dab tsi yog qhov zoo sib xws ntawm DNA thiab RNA. Rooj yuav ua tau ib tug indispensable cuab tam nyob rau hauv qhov kev xeem los yog ib tug yooj yim ceeb toom.

Nyob rau hauv tas li ntawd peb tau kawm ua ntej lawm nyob rau hauv lub rooj ib co ntawm qhov tseeb. Piv txwv li, lub peev xwm ntawm lub DNA ob yuav tsum tau rau cell division los kho ob hlwb tau txais kev tshuaj ntsuam genetic khoom nyob rau hauv nws txoj kev paub. Thaum RNA doubling nyob rau hauv tsis muaj kev txiav txim zoo. Yog hais tias koj xav tau lwm cell molecule, nws synthesizes nws DNA template.

Cov yam ntxwv ntawm DNA thiab RNA yuav tau txais ib nyuag, tab sis peb tau them tag nrho cov yam ntxwv ntawm cov qauv thiab cov nuj nqi. Heev ntawm nthuav cov neeg txhais lus txheej txheem - lub synthesis ntawm cov protein. Tom qab tau txais paub nws yuav ntshiab ua li cas loj ib lub luag hauj lwm no yog ua si los ntawm RNA nyob rau hauv lub cell lub neej. Ib tug txheej txheem ntawm doubling DNA heev exciting. Qhov ntawd tsuas yog lub tearing ntawm lub ob helix thiab nyeem ntawv txhua nucleotide!

Kawm tej yam tshiab txhua hnub. Tshwj xeeb tshaj yog yog hais tias nws yog tshiab nws yog tshwm sim nyob rau hauv txhua txhua cell ntawm koj lub cev.