Qauv thiab muaj nuj nqi ntawm DNA thiab RNA (Rooj)

Nws yog zoo dua lub npe hu hais tias tag nrho cov ntaub ntawv ntawm cov nyob qhov teeb meem, los ntawm cov kab mob thiab xaus dua tsiaj (xws li tib neeg) muaj ib tug tshwj xeeb raws roj ntsha apparatus. Nws yog sawv cev los ntawm molecules ntawm ob hom ntawm nucleic acids: deoxyribonucleic thiab ribonucleic. Nyob rau hauv cov organic tshuaj kho cov ntaub ntawv uas yog dhau los ntawm niam txiv rau cov xeeb ntxwv tib neeg nyob rau hauv tu tub tu kiv. Nyob rau hauv daim ntawv no, peb kawm txog cov qauv thiab cov kev ua ntawm DNA thiab RNA nyob rau hauv lub cell, raws li zoo raws li xav txog qhov mechanisms uas underlie cov kev ntawm kis tau tus mob ntawm roj ntsha thaj chaw ntawm nyob teeb meem.

Raws li nws muab tawm, lub thaj chaw ntawm nucleic acids, txawm hais tias lawv muaj ib co heev nta, txawm li cas los, txawv heev ntawm lawv tus kheej. Yog li ntawd peb piv rau DNA thiab RNA zog nqa tawm los ntawm cov neeg biopolymers nyob rau hauv lub hlwb ntawm txawv pab pawg ntawm cov kab mob. Lub rooj nyob rau hauv daim ntawv no yuav pab koj to taub dab tsi yuav tsum muaj sib txawv nruab nrab ntawm lawv.

Nucleic acids - complex biopolymers

Discoveries nyob rau hauv lub teb ntawm molecular biology uas uas tshwm sim nyob rau hauv lub ntxov thib nees nkaum xyoo pua, hauv particular, ntawv tseem ceeb ntawm cov qauv ntawm cov deoxyribonucleic acid, lub impetus rau txoj kev loj hlob ntawm cov niaj hnub cytology, noob caj noob ces, biotechnology thiab kev tshuaj ntsuam genetic engineering. Los ntawm qhov seem yus pom ntawm cov organic Science News for KIDS DNA thiab RNA muaj molecular tshuaj muaj repetitive units - monomers, kuj hu ua nucleotides. Nws yog lub npe hu hais tias lawv sib thooj, tsim tau ib Circuit Court peev xwm ntawm spatial self-lub koom haum.

Tej DNA macromolecules yog feem ntau txuam nrog kev nqaijrog muaj kev zog thiab hu ua histones. Nucleoprotein ceg tsim tshwj xeeb lug - nucleosomes, uas, nyob rau hauv lem, yog ib feem ntawm lub chromosome. Nucleic acids tej zaum yuav ob leeg nyob rau hauv lub nucleus thiab nyob rau hauv lub cytoplasm ntawm hlwb, ua tam sim no nyob rau hauv nyob tus yeees ntawm ib co ntawm nws cov organelles, xws li mitochondria los yog chloroplasts.

Lub spatial qauv ntawm cov tshuaj yeeb dej caw caj

Yuav kom nkag siab txog cov muaj nuj nqi ntawm DNA thiab RNA, nws yog tsim nyog los nkag siab nyob rau hauv kom meej lub peculiarities ntawm lawv cov qauv. Raws li nrog rau cov nqaijrog, nucleic acids yus muaj los ntawm ob peb theem ntawm lub koom haum ntawm macromolecules. Lub hom qauv yog sawv cev polynucleotide chains, theem nrab thiab tertiary configuration samouslozhnyayutsya tsob los ntawm covalent kev twb kev txuas hom. Ib tug tshwj xeeb lub luag hauj lwm nyob rau hauv kev tswj cov spatial puab ntawm lub lwg me me yog hydrogen bonds, Van ua dawb Waals rog thiab kev sib tshuam. Cov no ib tug compact qauv ntawm DNA, hu ua superspiral.

Monomers nucleic acid

Qauv thiab muaj nuj nqi ntawm DNA, RNA, cov nqaijrog, thiab lwm yam organic polymers nyob ntawm seb ob leeg nyob rau hauv qhov zoo thiab ntau pes tsawg leeg ntawm lawv macromolecules. Ob hom nucleic acids yog ua los ntawm cov yam ntxwv hais hu ua nucleotides. Raws li peb paub los ntawm lub chav kawm ntawm Science News for KIDS, qauv ntawm qhov teeb meem tas cuam tshuam nws txoj kev ua. DNA thiab RNA yog tsis muaj exception. Nws hloov tawm hais tias nyob rau hauv lub nucleotide muaj pes tsawg leeg nyob rau hauv daim ntawv ntawm cov acid nws tus kheej thiab nws cov luag hauj lwm nyob rau hauv lub cell. Txhua monomer muaj peb qhov chaw: ib tug nitrogenous puag, ib tug carbohydrate thiab lub qhov seem ntawm orthophosphoric acid. Muaj plaub hom nitrogenous bases ntawm DNA: adenine, guanine, thymine thiab cytosine. Nyob rau hauv RNA molecules, lawv yog, ntsig txog, adenine, guanine, cytosine thiab uracil. Carbohydrate sawv cev los ntawm ntau hom ntawm pentose. Lub ribonucleic acid yog ribose thiab nyob rau hauv DNA - nws deoxygenated daim ntawv no, hu ua deoxyribose.

Nta ntawm deoxyribonucleic acid

Ua ntej peb saib cov qauv thiab cov kev ua ntawm DNA. RNA muaj ib tug yooj yim spatial configuration, yuav tsum xyuas nyob rau hauv lub tom ntej no seem. Yog li ntawd, ob tug polynucleotide strands yog nyob rau ntawm ib tug pheej rov muaj dua hydrogen bonds tsim ntawm lub nitrogen bases. Nyob rau hauv ib ob peb ntawm "adenine - thymine," muaj ob, thiab nyob rau hauv ib tug khub ntawm "guanine - cytosine" - peb hydrogen bonds.

Conservative kab purine thiab pyrimidine bases twb nrhiav tau los ntawm E. Chargaff thiab lub npe hu ua lub hauv paus ntsiab lus ntawm complementarity. Lub ib saw nucleotides txuas phosphodiester bonds uas tsim ntawm lub pentose residue ntawm orthophosphoric acid thiab nyob ib sab nucleotides. Lub kauv daim ntawv ntawm ob chains yog tswj los ntawm hydrogen bonds uas tshwm sim nruab nrab ntawm cov hydrogen thiab cov pa atoms uas yog ib feem ntawm nucleotides. Ntau dua - tertiary qauv (supercoil) - cov yam ntxwv rau cov nuclear DNA ntawm eukaryotic hlwb. Nyob rau hauv daim ntawv no nws yog tam sim no nyob rau hauv lub chromatin. Txawm li cas los, cov kab mob thiab DNA uas muaj cov kab mob muaj deoxyribonucleic acid yog tsis txuam nrog proteins. Nws yog sawv cev los ntawm ib tug nplhaib zoo li tus daim ntawv thiab yog hu ua ib tug plasmid.

Nws muaj tib daim ntawv DNA ntawm mitochondria thiab chloroplasts - organelles, nroj tsuag thiab tsiaj hlwb. Tom qab ntawd peb nrhiav tau tawm, dab tsi yog qhov txawv ntawm ib tug muaj nuj nqi ntawm DNA thiab RNA. Cov nram qab no, qhia rau peb qhov sib txawv nyob rau hauv cov qauv thiab cov thaj chaw ntawm nucleic acids.

ribonucleic acid

Lub RNA molecule muaj ib zaug xwb polynucleotide strand (tshwj tsis yog rau ob npaug rau-tso tseg qauv ntawm ib co kab mob) uas yuav ua tau ob qho tib si nyob rau hauv lub nucleus thiab nyob rau hauv lub cytoplasm ntawm lub cell. Muaj ob peb hom ntawm RNA uas sib txawv ntawm ib tug qauv thiab zog. Yog li, tub txib RNA muaj lub siab tshaj plaws molecular ceeb thawj. Nws yog tsim nyob rau hauv lub cell nucleus nyob rau hauv ib tug ntawm cov noob. MRNA ua hauj lwm - mus rau cov hloov ntaub ntawv rau nyob tus yeees ntawm cov protein los ntawm cov keeb mus rau lub cytoplasm. Thauj daim ntawv nucleic acid hniav monomers cov nqaijrog - amino acids - thiab muab lawv mus rau lub site ntawm biosynthesis.

Thaum kawg, ribosomal RNA yog tsim nyob rau hauv lub nucleolus thiab yog muab kev koom tes nyob rau hauv protein synthesis. Raws li koj tau pom, DNA thiab RNA zog nyob rau hauv cellular metabolism yog ntau haiv neeg thiab tseem ceeb heev. Lawv yuav nyob ntawm seb feem ntau nyob rau hauv lub hlwb ntawm tus kab mob no uas yog yam qauv ntawm caj. Yog li ntawd, tus kab mob no ribonucleic acid tej zaum yuav ib cov cab kuj los ntawm caj ces, whereas nyob rau hauv lub hlwb ntawm eukaryotic kab mob no muaj peev xwm tsuas muaj deoxyribonucleic acid.

Muaj nuj nqi ntawm DNA thiab RNA nyob rau hauv lub cev

Nyob rau hauv nws cov nqi nucleic acid, nrog rau cov nqaijrog uas tseem ceeb organic tebchaw. Lawv khaws cia thiab kis roj ntsha yam ntxwv thiab cwj pwm los ntawm niam txiv rau cov xeeb ntxwv tib neeg. Wb txhais qhov txawv ntawm txhua lwm yam zog ntawm DNA thiab RNA. Cov nram qab no qhia tau hais tias qhov sib txawv nyob rau hauv ntau yam.

Yuav ua li cas yog cov yam ntxwv ntawm cov kab mob tshuaj ntawm caj?

Tus kab mob no nucleic acid tej zaum yuav siv rau hauv daim ntawv ntawm tag nrho ob qho single- thiab ob-strand qwj los yog rings. Raws li D.Baltimora kev faib tawm, cov khoom microcosm muaj DNA molecules muaj ib tug los yog ob tug circuits. Cov thawj pab pawg neeg no muaj xws li pathogens ntawm herpes thiab adenoviruses, thiab lub thib ob muaj xws li, piv txwv li, parvovirus.

Lub zog ntawm DNA thiab RNA kab mob muaj xws li nyob rau hauv allergic tus kheej kev tshuaj ntsuam genetic ntaub ntawv rau hauv ib lub cell, replication tshua molecules nqa kab nucleic acid, thiab lub rooj sib txoos uas muaj protein ntau hais nyob rau hauv lub ribosomes ntawm tus tswv tsev cell. Raws li ib tug tshwm sim, tag nrho cell metabolism yog kiag li subordinated mus rau lub cab uas muab sai heev, ua rau lub xovtooj ntawm txoj kev tuag.

RNA muaj cov kab mob

Nyob rau hauv virology ua qhov kev sib cais ntawm cov kab mob mus rau hauv ob peb pawg. Yog li ntawd, cov thawj hom hu ua ib leeg-tso tseg (+) RNA. Lawv nucleic acid ua tib zog raws li tus tub txib RNA ntawm eukaryotic hlwb. Nyob rau hauv lwm pab pawg neeg no muaj xws li ib leeg-tso tseg (-) RNA. Ua ntej, lawv molecules transcription tshwm sim, ua rau lub tsos ntawm molecules (+) RNA, thiab cov neeg nyob rau hauv lem, pab raws li template rau lub kab proteins.

Raws li cov foregoing, rau tag nrho cov kab mob, nrog rau cov kab mob, DNA thiab RNA zog luv luv yus li: cia raws roj ntsha yam ntxwv thiab cov khoom ntawm ib tug kab mob thiab qhov ntxiv kis tau tus mob ntawm lawv cov offspring.