Video: Yuav ua li cas prokaryotic hlwb muaj nyob rau hauv qhov chaw ntawm ib tug nucleus?
2024 Tus sau: Miles Stephen | [email protected]. Kawg hloov kho: 2023-12-15 23:36
Cov Prokaryotic Cell
Prokaryotes yog unicellular kab mob uas tsis muaj organelles los yog lwm yam nyob rau hauv daim nyias nyias-bound lug. Yog li ntawd, lawv ua tsis yog muaj a nucleus , tab sis, hloov, feem ntau muaj ib qho chromosome: ib daim ntawm cov voj voog, ob-stranded DNA nyob rau hauv ib cheeb tsam ntawm lub cell hu ua nucleoid
Tsuas yog li ntawd, cov cell prokaryotic puas muaj cov nucleus?
Kev faib nruab nrab prokaryotes thiab eukaryotes feem ntau suav hais tias yog qhov tseem ceeb tshaj plaws los yog qhov sib txawv ntawm cov kab mob. Qhov txawv yog tias eukaryotic hlwb muaj ib "true" nucleus muaj lawv DNA, hos prokaryotic cell ua tsis yog muaj nucleus . Prokaryotes tsis muaj mitochondria thiab chloroplasts.
Ib tug kuj yuav nug, ua li cas cov hlwb prokaryotic ciaj sia tsis muaj nucleus? Txawm tias prokaryotes ua tsis muaj ib nucleus (los yog lwm yam membrane-bound organelles), lub ua tseem muaj DNA. DNA yog ib lub voj, nyob rau hauv ib cheeb tsam ntawm lub cell hu ua thaj av nucleoid (saib daim duab). Reproduce lub cell , DNA voj yog replicated, thiab ib daim ntawv txav mus rau txhua sab ntawm lub cell ua ib feem ntawm binary fission.
Ntxiv mus, vim li cas cov hlwb prokaryotic tsis muaj nucleus?
Prokaryotes muaj lawv genomic DNA concentrated thiab localized mus rau ib cheeb tsam me me nyob rau hauv lub cell (lub cheeb tsam nucleoid). Yog li nws yog tsis yog tseeb kiag hais tias prokaryotes tsis muaj nucleus . Cov cell tuaj yeem tso DNAses mus rau hauv cytoplasm kom degrade tus kab mob DNA, nrog txo kev pheej hmoo ntawm degrading nws tus kheej DNA.
Lub nucleus ua dab tsi hauv lub cell prokaryotic?
Nucleoid Region Txawm tias lawv ua tsis muaj ib nucleus , prokaryotic hlwb tseem khaws lawv cov noob ntawm chromosomes thiab tseem tswj lawv cov DNA. Cov no hlwb nqa tawm ntau ntawm cov DNA no ua haujlwm nyob rau hauv ib qho chaw tshwj xeeb hu ua thaj av nucleoid. Lub cheeb tsam nucleoid muaj cov proteins thiab feem ntau tsuas yog ib ncig chromosome.
Pom zoo:
Yuav ua li cas yog lub sum ntawm cov atomic masses ntawm tag nrho cov atoms nyob rau hauv ib tug qauv rau ib tug compound?
Cov mis loj ntawm ib yam khoom yog qhov sib npaug ntawm qhov nruab nrab atomic masses ntawm txhua lub atom sawv cev hauv cov tshuaj formula thiab qhia nyob rau hauv atomic mass units. Cov mis loj ntawm covalent compound tseem hu ua molecular mass
Yuav ua li cas wavelength muaj feem xyuam rau qhov ceev ntawm lub teeb nyob rau hauv ib tug nruab nrab?
Qhov ceev ntawm lub teeb nyob rau hauv nruab nrab yog v = cn v = c n, qhov twg n yog nws qhov Performance index ntawm refraction. Qhov no txhais tau tias v = fλn, qhov twg λn yog lub wavelength nyob rau hauv nruab nrab thiab hais tias λn=λn λ n = λ n, qhov twg λ yog lub wavelength nyob rau hauv lub nqus tsev vacuum thiab n yog qhov nruab nrab qhov ntsuas ntawm refraction
Yuav ua li cas koj nrhiav tau qhov chaw ntawm lub voj voog nyob rau hauv ib tug conic seem?
Tus nqi ntawm r yog hu ua 'radius' ntawm lub voj voog, thiab qhov taw tes (h, k) hu ua 'center' ntawm lub voj voog. (h, k) = (0, 0), ces qhov sib npaug simplifiesto x2 + y2 = r2
Yuav ua li cas yog lub npe rau qhov chaw ntawm kev hla nyob rau hauv ib tug chromosome?
Hla dhau tshwm sim ntawm prophase I thiab metaphase I thiab yog tus txheej txheem uas ob homologous chromosome non-viv ncaus chromatids ua ke nrog ib leeg thiab sib pauv sib txawv ntawm cov khoom siv caj ces los ua ob qho kev sib txuas ntawm chromosome tus muam chromatids
Leej twg biologist tau qhia lub sij hawm prokaryote nyob rau hauv 1937 kom paub qhov txawv hlwb uas tsis muaj nucleus los ntawm nucleated hlwb ntawm cov nroj tsuag thiab tsiaj txhu?
Prokaryote / Eukaryote nomenclature tau thov los ntawm Chatton hauv 1937 los faib cov kab mob nyob rau hauv ob pawg loj: prokaryotes (cov kab mob) thiab eukaryotes (cov kab mob uas muaj cov cell nucleated). Tau txais los ntawm Stanier thiab van Neil qhov kev faib tawm no tau lees paub thoob ntiaj teb los ntawm cov kws tshawb fawb txog biologist txog tam sim no (21)