Koj puas tau hnov txog kev txawj ntse ntawm tes? Qhov no theej bold scientific hypothesis hais tias lub koom haum ntawm lub elementary chav tsev ntawm lub neej - lub cell - yog raug rau cov kev txawj ntse logical cov kev pab cuam. Lawv zoo ib yam li kev tswj hwm ntawm tib neeg lub cev los ntawm lub cev ua haujlwm nyuaj tshaj plaws - lub hlwb. Txhua lub cell organelles tsis yog tsuas yog muaj cov ntaub ntawv, cov qauv tsim kom muaj txiaj ntsig, tab sis kuj muaj peev xwm ua haujlwm tshwj xeeb. Lawv muab tag nrho cov txheej txheem tseem ceeb ntawm cellular biosystem: nws cov khoom noj khoom haus, kev loj hlob, kev faib, thiab lwm yam. Hauv peb tsab xov xwm, peb yuav xav txog cov cell organelles li ribosomes. Lawv lub luag haujlwm yog nyob rau hauv kev sib txuas ntawm cov organic tebchaw tseem ceeb ntawm cov cell - proteins.
Me me tab sis daring
Cov neeg hais lus no yog qhov zoo tshaj plaws rau cov cellular organelle - ribosome. Pom tau nyob rau hauv 1953, nws yog suav hais tias yog qhov tsawg tshaj plaws cellular qauv, thiab nyob rau hauv tas li ntawd mus tsis muaj daim nyias nyias. Qhov ribosomes tseem ceeb heev tuaj yeem ua pov thawj los ntawm qhov tseeb yooj yim hauv qab no. Txhua lub hlwb tsis muaj kev zam: tsiaj txhu, nroj tsuag, fungi, thiab txawm tias tsis yog-nuclearkab mob - muaj ib tug loj tus naj npawb ntawm ribosomes. Cov synthesis ntawm cov protein ua los ntawm lawv muab cov cell nrog cov proteins uas ua lub tsev, tiv thaiv, catalytic, signaling thiab ntau lwm yam dej num nyob rau hauv nws.
Qhov loj ntawm ib lub cev tsis pub tshaj 20 nm, nws txoj kab uas hla yog li 15 nm, thiab nws cov duab zoo ib yam li cov khoom ua si kheej kheej - tus menyuam roj hmab zes. Txhua subunit yog tsim nyob rau hauv lub cell nucleus uas muaj cov nucleolus. Qhov no yog qhov chaw ntawm synthesis ntawm ribosome hais. Cia peb nyob ntawm cov qauv ntawm cov protein-synthesizing apparatus ntawm lub cell kom ntxaws.
Dab tsi nyob hauv
Ribosome muaj ob lub subunits, hu ua loj thiab me. Txhua ntawm lawv muaj cov proteins tshwj xeeb cuam tshuam nrog ribonucleic acid molecules. Cov subunits ntawm lub organoid, zoo li ob lub puzzles, sib koom ua ke nyob rau hauv lub sij hawm ntawm protein synthesis, thiab tom qab nws ua tiav lawv tau sib cais, seem nyob rau hauv lub cytoplasm ntawm lub cell.
Raws li tau hais ua ntej, RNA yog ib feem ntawm ribosome. Lub subunit loj ntawm lub organelle muaj peb nucleic acid molecules txuas nrog 35 peptide molecules, ib qho RNA molecule ntawm cov khoom me me yog txuam nrog 20 cov protein. Ua ntej peb tau hais txog qhov tseeb tias tus lej ntawm ribosomes loj. Nws yog ncaj qha proportional rau qhov kev siv ntawm cov protein biosynthesis txheej txheem tshwm sim nyob rau hauv lub cell. Yog li, nyob rau hauv tib neeg thiab feem ntau vertebrates, qhov loj tshaj plaws tsub zuj zuj ntawm organelles yog pom nyob rau hauv lub hlwb ntawm cov pob txha liab thiab hepatocytes - lub structural units ntawm lub siab.
YRibosome proteins
Organelle proteins yog heterogeneous nyob rau hauv lawv tus kheej txoj kevamino acid muaj pes tsawg leeg, yog li ntawd, txhua cov protein molecule nruj me ntsis khi tsuas yog rau ib feem ntawm ribosomal ribonucleic acid. RNA molecule tsim nyob rau hauv lub nucleolus txuas nrog cov proteids nyob rau hauv lub tertiary configuration los ntawm ntau covalent bonds. Ntawm no, nyob rau hauv lub nucleolus ntawm lub cell nucleus, tsim ntawm subunits ntawm lub organoid tshwm sim. Yog li, muaj pes tsawg leeg ntawm ribosomes suav nrog ob hom polymers, uas yog cov proteins thiab ribonucleic acid. Nyob rau hauv kev npaj rau biosynthesis, ribosomes ua ke nrog ib tug molecule ntawm cov ntaub ntawv ribonucleic acid, uas ua rau tsim ib tug complex qauv - polysomes.
Tus naj npawb ntawm cov organelles zaum ntawm RNA saw yuav sib haum rau cov protein molecules nrog tib cov amino acid muaj pes tsawg leeg.
Tshaj tawm
Cov txheej txheem hluavtaws ua rau kev tsim cov khoom kawg - cov protein - suav nrog hauv pab pawg ntawm cov tshuaj tiv thaiv assimilation thiab hu ua kev txhais lus. Lub luag haujlwm ntawm ribosomes hauv nws yog dab tsi? Qhov pib ntawm biosynthesis yog tus cwj pwm los ntawm qhov tseeb tias kev pib yog nqa tawm - kev sib txuas ntawm cov ntaub ntawv ribonucleic acid nrog lub subunit me me ntawm organoid. Nyob rau hauv lub cell cytoplasm, ib tug ribosome yog txuas mus rau ib qho ntawm lub davhlau ya nyob twg seem, uas yog lub teeb liab rau cov txheej txheem ntawm biosynthesis. Cov theem tom ntej, elongation, muaj nyob rau hauv kev sib cuam tshuam ntawm ribosome nrog thawj ob RNA hais, hu ua thauj sawv daws yuav. Lawv, zoo li lub tsheb tavxij thauj khoom, xa cov amino acids mus rau lub cev, uas tom qab ntawd txav mus rau hauv cov saw hlau polynucleotide.
Tib lub sijhawm, cov amino acids txuas rau ib leeg nrog kev pab ntawm peptide bonds, ua rau muaj kev nce hauv cov protein molecule. Qhov kawg theem - kev txiav tawm, muaj nyob rau hauv lub fact tias nyob rau hauv lub chav kawm ntawm lub organelle lub zog raws lub mRNA nws ntsib ib tug nres codon, piv txwv li, UAA, UGA los yog UAG. Nyob rau hauv thaj tsam ntawm cov triplets no, muaj kev tawg ntawm covalent bonds ntawm cov protein thiab cov t-RNA kawg. Qhov no ua rau kev tso tawm ntawm peptide los ntawm polysome. Yog li, ribosome yog cov khoom tseem ceeb ntawm cov cell, muab cov synthesis ntawm nws cov proteins.
Hauv peb tsab xov xwm, peb pom tias cov organic polymers tsim ribosomes, thiab kuj txiav txim siab lawv lub luag haujlwm hauv lub neej ntawm tes.
