Yuav ua li cas zog nyob rau hauv ib lub cell ua nucleic acid? Tus qauv thiab muaj nuj nqi ntawm nucleic acids

Nucleic acids ua si ib qho tseem ceeb luag hauj lwm nyob rau hauv lub cell, kom ntseeg tau nws hauj lwm thiab tu tub tu kiv. Cov zog ua rau nws tau mus hu xov tooj rau lawv lub thib ob feem ntau tseem ceeb biomolecules tom qab protein. Muaj ntau soj ntsuam ntawm txawm coj tawm lub DNA thiab RNA nyob rau hauv thawj qhov chaw, lub ntsiab lus lawv tus thawj xibfwb nqi nyob rau hauv txoj kev loj hlob ntawm lub neej. Cuaj kaum, lawv yog cov yuav coj lub thib ob qhov chaw tom qab cov proteins, vim hais tias lub hauv paus ntawm lub neej yog cia li polipetidnaya molecule.

Nucleic acids - qhov no yog ib tug txawv theem ntawm lub neej yog ntau npaum li cas complex thiab nthuav vim hais tias ntawm qhov tseeb hais tias txhua yam ntawm molecule muaj ib tug meej txoj hauj lwm rau nws. Qhov no yog tsim nyog los nkag siab rau ntau yam.

Lub tswvyim ntawm cov nucleic acids

Tag nrho cov nucleic kua qaub (DNA thiab RNA) yog lom heterogeneous polymers uas txawv nyob rau hauv lub xov tooj ntawm circuits. DNA yog ib tug muab ob npaug rau tso tseg polymeric molecule uas muaj caj ces cov ntaub ntawv ntawm eukaryotic kab mob. Yeej DNA molecule tej zaum yuav muaj kev tshuaj ntsuam genetic cov ntaub ntawv ntawm ib co kab mob. Qhov no kab mob HIV thiab adenovirus. Muaj kuj yog ib tug tshwj xeeb ntaus 2 DNA: mitochondrial thiab plastid (pom nyob rau hauv chloroplasts).

RNA kuj muaj ib tug loj npaum li cas hom uas yog tshwm sim los ntawm ntau nucleic acid zog. Muaj nuclear RNA, uas muaj cov kev tshuaj ntsuam genetic cov ntaub ntawv ntawm cov kab mob thiab feem ntau cov kab mob, lub matrix (los yog cov tub txib RNA), ribosomal thiab thauj. Tag nrho cov ntawm lawv yog muab kev koom tes nyob rau hauv yog cia ntawm caj ces, los yog noob qhia. Txawm li cas los, uas zog nyob rau hauv ib lub cell khiav lag luam nucleic acid yog tsim nyog los nkag siab nyob rau hauv ntau dua kom meej.

Muab ob npaug rau tso tseg DNA molecule

Qhov no hom ntawm DNA - yog ib tug zoo meej zog ntawm cia ntawm kev tshuaj ntsuam genetic ntaub ntawv. Muab ob npaug rau tso tseg DNA molecule yog ib tug hluas molecule muaj ua kev monomers. Lawv lub hom phiaj yog lub tsim ntawm hydrogen bonds ntawm nucleotides ntawm lwm chains. Self DNA monomer muaj ib tug nitrogenous puag, lub qhov seem orthophosphate thiab ib tug tsib-carbon monosaccharide deoxyribose. Nyob ntawm seb dab tsi hom ntawm nitrogen puag yog lub hauv paus ntawm kev DNA monomer, nws muaj nws tus kheej lub npe. Hom ntawm DNA monomers:

• deoxyribose moiety nrog lub orthophosphate thiab adenylic nitrogenous puag;
• thymidine nitrogenous puag thiab tus deoxyribose moiety orthophosphate;
• cytosine nitrogenous puag thiab lub qhov seem desoksiriboza orthophosphate;
• orthophosphate nrog deoxyribose thiab nitrogenous guanine residue.

Cov tsab ntawv rau simplification ntawm Circuit Court qauv ntawm DNA adenylic residue denoted li "A", guanine - "G", thymidine - "T" thiab cytosine - "C". Nws yog ib qho tseem ceeb tias cov kev tshuaj ntsuam genetic ntaub ntawv yog kis los ntawm cov double-tso tseg DNA mus rau hauv cov tub txib RNA. Txawv nyob rau hauv nws me ntsis: ntawm no raws li cov carbohydrate moiety tsis tau deoxyribose thiab ribose, thiab es tsis txhob thymidylic nitrogenous puag uracil tshwm sim nyob rau hauv RNA.

Qauv thiab muaj nuj nqi ntawm DNA

DNA yog ua nyob rau hauv lub hauv paus ntsiab lus ntawm ib tug lom polymer, nyob rau hauv uas ib tug saw yog tsim nyob rau hauv ua ntej nyob rau hauv ib tug predetermined qauv nyob rau hauv lub caj cov ntaub ntawv ntawm cov niam txiv ntawm tes. DNA Nukleodidy yog kev cob cog rua ntawm covalent bonds. Ces, raws li lub hauv paus ntsiab lus ntawm complementarity mus rau lub nucleotides ntawm ib leeg-tso tseg molecules yog koom los ntawm lwm yam nucleotides. Yog hais tias ib tug ib leeg-tso tseg nucleotide molecule yog hais pib nrog adenine, qhov thib ob (complementary) Circuit Court nws yuav sib haum mus rau thymine. Guanine yog complementary rau cytosine. Yog li, muab ob npaug rau-tso tseg DNA molecule yuav ua lub tsev. Nws yog nyob rau hauv lub noob pob kws thiab khw muag khoom raws roj ntsha cov ntaub ntawv uas yog kho codons - triplets ntawm nucleotides. Lub zog ntawm cov double-tso tseg DNA:

• Txuag tau los ntawm cov niam txiv ntawm tes raws roj ntsha ntaub ntawv;
• noob qhia;
• chaw khuam siab hloov qhov xwm ntawm tus hloov.

Lub ntsiab lus ntawm cov nqaijrog thiab nucleic acids

Nws yog ntseeg hais tias cov kev ua ntawm cov nqaijrog thiab nucleic acids ntau, namely, lawv muab kev koom tes nyob rau hauv noob qhia. Nucleic acid nws tus kheej - nws yog lawv cia qhov chaw thiab lub protein - nws yog ib lub kawg ntawm kev nyeem ntawv ntaub ntawv los ntawm ib lub noob. Noob nws tus kheej yog ib feem ntawm ib tug DNA molecule fej nyob rau hauv lub chromosome, nyob rau hauv cov ntaub ntawv uas yog sau cia los ntawm nucleotides ntawm tus qauv ntawm ib qho kev protein. Ib tug noob encodes cov amino acid ib theem zuj zus ntawm tsuas yog ib qho protein. Uas muaj protein ntau yuav siv lub roj ntsha ntaub ntawv.

Cov kev faib ntawm hom ntawm RNA

Tso cai ntawm nucleic acids nyob rau hauv lub cell yog heev ntau haiv neeg. Thiab lawv yog cov feem ntau heev heev nyob rau hauv cov ntaub ntawv ntawm RNA. Txawm li cas los, qhov no multifunctionality yog tseem txheeb ze vim hais tias raws li ib hom ntawm RNA yog lub luag hauj lwm rau ib tug ntawm lub zog. Nyob rau hauv cov ntaub ntawv no, lub nram qab no ntawm RNA:

• nuclear RNA cov kab mob thiab cov kab mob;
• matrix (ntaub ntawv) RNA;
• ribosomal RNA;
• tub txib RNA plasmids (lub chloroplast);
• chloroplast ribosomal RNA;
• mitochondrial ribosomal RNA;
• mitochondrial matrix RNA;
• hloov RNA.

RNA zog

Qhov no kev faib muab ob peb hom RNAs uas raug muab faib raws li qhov chaw nyob. Txawm li cas los, nyob rau hauv tej qhov lus, lawv yuav tsum tau muab faib ua 4 hom nyob rau hauv tag nrho cov: nyob rau hauv lub nuclear, ntaub ntawv, ribosomal thiab thauj. Ribosomal RNA muaj nuj nqi yog protein synthesis raws li nyob rau hauv lub nucleotide ib theem zuj zus ntawm cov tub txib RNA. Yog li amino acid "Tais" rau ribosomal RNA "strung" rau tus tub txib RNA, los ntawm txoj kev hloov mus rau lwm ribonucleic acid. Yog li ntawd synthesis tau nyaij los ntawm tej kab mob uas muaj cov ribosome. Tus qauv thiab muaj nuj nqi ntawm nucleic acids thiab muab preservation ntawm lub caj cov khoom, thiab ua lub protein synthesis txheej txheem.

Mitochondrial nucleic acid

Yog hais tias yog dab tsi zog nyob rau hauv lub cell ua nucleic acid nyob rau hauv lub nucleus los yog cytoplasm ntawm zoo siv tag nrho cov paub, ntawm mitochondrial thiab plastid DNA ntaub ntawv, muaj me ntsis. Nws kuj muaj nyob tej ribosomal thiab cov tub txib RNA. Lub nucleic acids DNA thiab RNA yog tam sim no no txawm lub feem ntau autotrophic kab mob.

Tej zaum qhov nucleic acid nkag mus rau hauv cell los ntawm symbiogenesis. Qhov no txoj kev yog xam los ntawm zaum raws li cov feem ntau yuav vim hais tias ntawm cov tsis muaj lwm txoj kev piav qhia. Cov txheej txheem yog suav tias yog raws li nram no: nyob rau hauv lub cell rau ib tug tej lub sij hawm tuaj symbiontic avtorofnaya kab mob. Raws li ib tug tshwm sim, qhov no akaryote nyob hauv hlwb thiab muab nws nrog lub zog, tab sis maj mam degrades.

Nyob rau hauv thawj zaug rau theem ntawm evolution, tej zaum nuclear-free symbiotic kab mob tsiv mutational dab nyob rau hauv lub nucleus ntawm tus tswv tsev cell. Qhov no tso cai rau noob lub luag hauj lwm rau kev tswj cov lus qhia txog cov qauv ntawm cov mitochondrial proteins uas kom txeem mus rau hauv lub nucleic acid ntawm tus tswv tsev cell. Txawm li cas los, nws yog hais txog dab tsi zog nyob rau hauv lub cell ua nucleic acids ntawm mitochondrial keeb kwm, cov ntaub ntawv yog tsis ntau.

Tej zaum nyob rau hauv ib feem mitochondrial tsim cov nqaijrog uas nws qauv tau tseem tsis tau kho los ntawm nuclear DNA los yog RNA party. Nws yog tseem yuav hais tias cov mechanism ntawm protein synthesis yog tsim nyog xwb vim hais tias cov cell hais tias muaj ntau cov nqaijrog tsim nyob rau hauv lub cytoplasm, yuav tsis tau los ntawm lub ob daim nyias nyias ntawm lub mitochondria. Cov ntaub ntawv organelles zog, thiab yog li ntawd nyob rau hauv cov ntaub ntawv ntawm ib lub channel los yog transporter protein rau nws txaus rau molecular tsab ntawv tsa suab thiab tawm tsam ib tug concentration gradient.

Plasmid DNA thiab RNA

Nyob rau hauv plastids (chloroplasts) kuj muaj nws tus kheej DNA, uas tej zaum yog lub luag hauj lwm rau kev siv zoo xws li cov zog raws li nyob rau hauv cov ntaub ntawv ntawm mitochondrial nucleic acids. Muaj kuj yog thiab nws ribosomal, matrix thiab hloov RNA. Thiab plastids, judging los ntawm tus xov tooj ntawm week, es los ntawm tus xov tooj ntawm biochemical kev tig cev, tsis yooj yim mus nrhiav tau. Nws tshwm sim hais tias muaj ntau plastids nrog 4 daim nyias nyias txheej, uas yog piav los ntawm kws tshawb fawb nyob rau hauv ntau txoj kev.

Ib yam yog tseeb: cov nuj nqi ntawm nucleic acid mus rau lub hlwb kawm kom deb li deb insufficiently. Nws tsis yog lub npe hu li cas ib qho tseem ceeb cov mitochondrial protein synthesizing system thiab zoo sib xws rau nws hloroplasticheskaya. Nws tseem yog tsis meej vim li cas lub hlwb xav tau mitochondrial nucleic acid, yog tias cov nqaijrog (obviously tsis yog txhua txhua) twb encoded nyob rau hauv lub nuclear DNA (los yog RNA, nyob ntawm seb tus kab mob). Txawm tias ib co ntawm cov lus muaj tseeb yog yuam kom lees tias cov protein synthesizing mitochondrial thiab chloroplast system yog lub luag hauj lwm rau tib lub zog li lub DNA ntawm lub nucleus thiab cytoplasm RNA. Lawv khaws cia caj ces, cov me nyuam thiab xa nws mus rau tus ntxhais lub hlwb.

txoj kev

Nws yog ib qho tseem ceeb kom nkag siab txog uas kev khiav dej num nyob rau hauv ib lub cell ua nucleic acid nuclear, plastid thiab mitochondrial keeb kwm. Qhov no yuav qhib li ntau zeem muag rau science, vim hais tias cov symbiotic mechanism, raws li uas muaj ntau autotrophic kab mob uas muaj peev xwm muaj me tub niaj hnub no. Qhov no yuav muab ib yam tshiab ntawm hlwb, tej zaum txawm tib neeg. Txawm tias lub zeem muag ntawm kev siv mnogomembrannyh plastid organelles nyob rau hauv lub hlwb ib yam nkaus thiab thaum ntxov hais.

Ntau npaum li cas ib qho tseem ceeb yog kom to taub tias nyob rau hauv lub cell nucleic acids lub luag hauj lwm rau yuav luag tag nrho cov dab. Qhov no protein biosynthesis, thiab txuag cov lus qhia txog cov qauv ntawm cov hlwb. Thiab tseem ceeb tshaj mas, lub nucleic acid khiav lub hloov lwm lub tsev muaj nuj nqi ntawm lub roj ntsha khoom siv ntawm lub hlwb los ntawm niam txiv rau tus me nyuam. Qhov no yuav xyuas kom meej ntxiv kev loj hlob ntawm evolutionary dab.