Shin, kun san cewa duk sel a yau sun samo asali ne daga tantanin halitta daya? Duniya mai ban mamaki na sel, wanda aka yi nazari ta wani reshe na kimiyya, ilimin halitta, yana ba mu damar fahimtar halaye na ainihin sashin rayuwa: tantanin halitta.
Tare da taimakon microscopy, yana yiwuwa a kwatanta bayyanar m da aikin sel, da kuma fahimtar ainihin kaddarorin su, ƙyale masana kimiyya su bambanta tsakanin nau'in sel guda biyu: prokaryotes da eukaryotes. A nan za mu gaya muku bambanci tsakanin eukaryotic da prokaryotic Kwayoyin, da kuma kadan game da duniyar Kwayoyin.
Gabatarwa: bambanci tsakanin eukaryotic da prokaryotic Kwayoyin
Babban bambanci tsakanin ƙwayoyin eukaryotic da prokaryotic ya dogara da su girma da kuma na kasancewar ko rashi na wasu kwayoyin halitta da tsarin salula.
- Gabaɗaya, zamu iya ƙayyade hakan Kwayoyin eukaryotic sun fi girma (fiye da 10 micrometers) kuma mafi hadaddun fiye da ƙwayoyin prokaryotic, waɗanda ba su da ƙasa da milimita 10 a girman kuma mafi sauƙi a tsari.
- El ainihin, shine inda ADN wanda ke bayyana tantanin halitta. Yana wanzu ne kawai a cikin ƙwayoyin eukaryotic, kamar yadda cytoskeleton da sauran kwayoyin halitta kamar mitochondria, chloroplasts, da vacuoles.
- A daya bangaren kuma, hanyar rayuwa kwayoyin halitta masu zaman kansu unicellular siffa ce ta kwayoyin prokaryotic. Yayin cikin Kwayoyin eukaryotic wasu ne unicellular zauna lafiya kuma wasu kuma hadaddun kwayoyin halitta masu yawa.
- Wani bangare na banbance tsakanin wadannan kwayoyin halitta shine haifuwa. Kwayoyin prokaryotic ko da yaushe suna haifuwa ta hanyar jima'i, yayin da a cikin eukaryotes akwai nau'o'in tsarin haifuwa guda biyu: jima'i da jima'i.
Kamanceceniya Tsakanin Kwayoyin Eukaryotic da Prokaryotic
Baya ga bambance-bambancen da aka lura a cikin batu na baya, akwai wasu kamance tsakanin kwayoyin eukaryotic da kwayoyin prokaryotic waɗanda za mu ambata a ƙasa:
- Dukansu ƙwayoyin eukaryotic da ƙwayoyin prokaryotic su ne asali da asali raka'o'in rayuwa a duniya. Saboda wannan gaskiyar, kowane ɗayan kwayoyin halitta daban-daban na unicellular da multicellular sun sami damar haɓakawa da mamaye wurare daban-daban a duniya.
- Waɗannan nau'ikan tantanin halitta guda biyu suna siffanta su da a tsarin da membrane ke ƙunshe a cikinsa DNA ko bayanan kwayoyin halitta. Kuma nau'ikan enzymatic daban-daban waɗanda ke ba su damar aiwatar da mahimman ayyukansu: ciyarwa, girma da haɓakawa.
- Kwayoyin Eukaryotic da prokaryotic, don rayuwa da haɓakawa, Suna ci gaba da juyar da makamashi daga wannan nau'i zuwa wani. Bugu da ƙari, ci gaba da ci gaba da dangantaka da na waje don amsa daban-daban bayanan kimiyya-kwayoyin halitta da suke samu daga muhallinsu.
Menene kwayar prokaryotic?
An samo sunanta daga kalmar Helenanci "pro", wanda ke nufin "a da", yana nufin kasancewarsa kafin bayyanar wasu nau'in tantanin halitta eukaryotic. Idan muka kalli tarihin juyin halitta na halittu, Kwayoyin prokaryotic sune mafi yawan sel daban-daban kuma mafi sauƙi kuma mafi tsufa.
Kwayoyin prokaryotic daban-daban waɗanda ke rayuwa a kusan duk wuraren zama a duniya na cikin mulkin monera, wanda kwayoyin cuta ne (eubacteriada archaea (bakuna).
Halayen sel prokaryotic
Don ganin ciki kwayoyin prokaryotic kana bukatar ka yi shi da a microscope na lantarki, domin ita ce mafi girman ƙuduri. Kwayoyin prokaryotic suna da tsari mafi sauƙi kuma mafi ƙanƙanta. Ciki na kwayar prokaryotic ya dogara ne akan:
- Plasma membrane. Kamar kowane sel, an kewaye shi da membrane. Ya ƙunshi folds da ake kira lamellae. Wannan tsarin yana ba tantanin halitta babban ƙarfin musanya abubuwan gama gari tare da sauran halittu ta hanyar su.
- mesosomes. Ciwon ƙwayar ƙwayar ƙwayar ƙwayar cuta, wanda ke da alaƙa da rabon tantanin halitta.
- Bangon sel. Ita ce mafi girman gefen tantanin halitta, kuma yana ba shi kariya.
- Cytoplasm. Wannan shine yanayin ciki a cikin tantanin halitta. Yana da yanayin ruwa-danko. Wannan shi ne inda kwayoyin halitta da kwayoyin sinadarai na tantanin halitta suke.
- nucleoid. Mafi girman yanki na cytoplasm inda aka samo DNA ta salula, ko kayan halitta. Ba kamar a cikin ƙwayoyin eukaryotic ba, DNA a nan ba ta rabu da sauran sassan tantanin halitta.
- Ribosomes. Wadannan sifofi suna da aikin kera kwayoyin halitta irin su sunadaran. Suna iya zama 'yanci a cikin cytoplasm, ko kafa ƙungiyoyi (polyribosomes).
- Cilia, flagella ko fibrils. Su ne tsarin waje na tantanin halitta, wanda ke ba su damar motsawa.
Su ilimin halittar jiki Yana da canji (Spherical, karkace ko sanda, da sauransu). Kuma yanayin haifuwarsu shine mai haila, wanda ke sa su rarraba cikin sauri.
Menene kwayar eukaryotic?
Ma'anar eukaryote ta fito ne daga Girkanci, inda "Yau" yana nufin "gaskiya" kuma "karyon" yana nufin "core". Ta wannan hanyar, babban halayen da ke bayyana a cell eukaryotic shi ne kasancewar tsakiya na gaskiya a cikin tsarin salularsa, wanda ke bayyanawa da kuma kiyaye DNA ta tantanin halitta. Bugu da ƙari, kasancewa mafi girma, sun fi rikitarwa a cikin ilimin halittarsu da aikinsu.
Halayen kwayar eukaryotic
Siffofin sel eukaryotic mun gano cewa suna da tsari mai yawa kuma hadaddun tsarin gabobin. Wasu gabobin sun keɓanta ga ƙwayoyin dabba ko shuka, wasu kuma na kowa ga duka biyun.. A gaba, za mu ambaci manyan su:
- Plasma membrane. iyakar iyakar tantanin halitta. Ayyukansa shine musayar kwayoyin halitta da sinadarai tsakanin waje da ciki na tantanin halitta. Ya ƙunshi nau'i biyu na phospholipids da sunadarai. Akwai nau'ikan sunadarai na membrane iri biyu:
- sunadaran transmembrane: keta lipid bilayer daga gefe zuwa gefe. Suna da ayyuka daban-daban, misali, jigilar abubuwa da kwayoyin halitta daga wajen tantanin halitta.
- Protein na gefe: suna sadarwa ne kawai tare da ciki ko waje na tantanin halitta. - Kwayoyin tsakiya. A nan ne aka samo DNA ko kwayoyin halitta na tantanin halitta. An raba shi da cytoplasm da ƙwayar nukiliya, wannan shine sau biyu.
- Membrane na nukiliya. Tsarin ne wanda ke raba tsakiya tantanin halitta da sauran cytoplasm. Tana da ramuka, da ake kira pores na nukiliya, waɗanda ke ba da damar musayar kwayoyin halitta.
- nucleolus. Ita ce bangaren tsakiya na tsakiya. Ita ce ke da alhakin kera abubuwan da suka hada da ribosomes.
Chromosomes, menene su?
Ana samun su a cikin tsakiya, kuma stare da raka'o'in da suka yi DNA. A cikin core an nade da tarihi (proteins) da kuma ADN don haka samar da chromatin.
A lokacin mafi yawan zagayowar rayuwar tantanin halitta, chromatin yana cikin yanayin barci. Amma a wani lokaci, sai ya fara murɗawa kuma ya ɗanɗana. DNA ta nannade kanta da sunadaran sau da yawa cewa yayi kama da m. Kamar dai ka ɗauki mita na waya ka fara nannade ta sosai kamar yadda zai yiwu. Suna ƙarewa da ƙaramin ƙwallon ƙafa. A cikin wannan sabon ƙaramin yanayi, chromatin yana sake tsarawa zuwa gaɓoɓin jikin da ake kira chromosomes.
Don haka, kasancewar DNA ta ƙunshi. ya ƙunshi bayanan kwayoyin halitta. Misali, akan daya daga cikin chromosomes zaku sami bayanai game da launin gashi, wani kuma yana iya zama bayanin tsayin jiki, da sauransu.
Kowace kwayar halitta ta ƙunshi bayanan kwayoyin halitta daban-daban, kuma adadin chromosomes zai zama nau'in nau'i.. A cikin mutane, kowane tantanin halitta a jikinmu yana dauke da chromosomes 46. Kusan dangi na chimpanzees suna da chromosomes 48 a cikin ƙwayoyin su. Ya kamata a lura da cewa a cikin eukaryotic Kwayoyin, yawan chromosomes ne ko da yaushe ko da. Akwai nau'o'in chromosomes iri ɗaya guda biyu, kuma chromosomes masu girma, siffar, da bayanan kwayoyin halitta iri ɗaya an haɗa su zuwa nau'i-nau'i da ake kira. nau'i-nau'i na chromosomes masu kama da juna ko kuma nau'i-nau'i masu kama.
Sauran sassan da ke daure membrane na sel eukaryotic
La membrane na ciki Kwayoyin eukaryotic suna ƙayyade yanayi daban-daban waɗanda ayyuka daban-daban ke faruwa. Yana kama da masana'anta, yana yin ayyuka a wurare daban-daban don haɓaka aiki. Daga cikin kwayoyin da ke daure membrane shine endoplasmic reticulum (ER). Yana da kamannin labyrinth, kuma membrane yana hade da tsakiya. Bambance yankunan lattice da ke hade da ribosomes.
da ribosomes suna manne da saman farfajiyar membrane na reticular, suna ba shi m ko granular bayyanar. Yankin reticular da ke hade da ribosome, wanda ke da aikin yin sunadarai, ana kiransa m ko granular endoplasmic reticulum (RER ko REG). Ana kiran ɓangaren lattice wanda ba ya ƙunshi ribosomes santsi endoplasmic reticulum (SER) kuma, a tsakanin sauran abubuwa, yana da aikin kera lipids.
El Golgi hadaddun wata gabobin ce da ke da siffa kamar rumbun tsumma. Wasu sunadaran da aka samar a cikin RER sun zo nan kuma an gyara su. Kayayyakin suna zuwa wurare daban-daban: na'urar Golgi shi ne mai kula da jigilar sunadarai da kwayoyin halitta ke samarwa.
Wasu suna zuwa membrane na plasma, wasu sunadaran za a fitar da su zuwa wasu kwayoyin halitta, yayin da wasu za a tattara su a cikin 'yan kananan jakar membrane da ake kira. vesicles. A lysosomes su ne nau'i na musamman na vesicles da aka samar a cikin rukunin Golgi masu dauke da enzymes da ke taka rawa wajen lalata kwayoyin halitta masu shiga cikin kwayoyin halitta. Ana kiran wannan tsari narkewar salula.
Mitochondria
An kewaye su da a biyu membrane. Membran ciki na mitochondria yana da folds da yawa da ake kira tuddai. A cikin mitochondrial matrix ana samun kwayoyin halitta DNA da ribosomes. A cikin mitochondria, ana aiwatar da halayen sinadaran da ke ba da damar samar da makamashin sinadarai daga kwayoyin halitta a gaban iskar oxygen. Wannan makamashi shi ne ke ɗora duk mahimman hanyoyin tafiyar da tantanin halitta.
Chloroplasts
akwai kawai a cikin ƙwayoyin shuka. Yana da membrane na waje, membrane na ciki, da nau'in membrane na uku a cikin nau'i na lallausan jakar da ake kira. thylakoids Suna kama da faranti da aka tattara. Ana kiran kowane ɗayan waɗannan tari talla. Thylakoids sun ƙunshi Chlorophyll, launin kore mai launin kore wanda ke ba da damar aiwatar da tsari tsarin photosynthesis.
vacuoles
Su ne membranous vesicles samuwa a cikin dabbobi da shuka Kwayoyin. Duk da haka, su ne mafi mahimmanci a cikin kwayoyin halitta. Za su iya mamaye har zuwa 70-90% na cytoplasm. Gabaɗaya, aikinsa shine ajiya.
Ribosomes
Su kwayoyin halitta ne da aka samu daga rukunoni guda biyu (manjo da kanana) wadanda suka samo asali daga cikin nucleolus, kuma da zarar a cikin cytoplasm, an hada su don yin ayyukansu. Ribosomes su ne alhakin samar ko hada sunadarai. Suna sakin su cikin cytoplasm ko kuma su ɗaure saman RER.
Cytoskeleton
A cikin cytoplasm na sel eukaryotic, akwai nau'ikan filaments na musamman waɗanda ke yin cytoskeleton, kuma waɗannan filaments sune. da ake buƙata don kula da siffar tantanin halitta da kuma riƙe organelles a wurin. Tsari ne mai matuƙar ƙarfi yayin da yake ci gaba da tsarawa da tarwatsewa, yana ba da damar sel su canza siffar (misali, ga waɗanda ke da motsi) ko gabobin jiki don motsawa cikin cytoplasm.
centrioles
Tsari ne guda biyu da aka kafa ta filaments da samu a cikin cytoplasm na dabba Kwayoyin. Suna shiga cikin rarraba tantanin halitta.
Bangon sel
Na musamman don dasa sel. Yana waje da membrane na plasma kuma yana ba da kariya. Tsarinsa ya bambanta da na bangon tantanin halitta na sel prokaryotic. Zubar da wasu mahadi akan bangon tantanin halitta yana ba da sassan shuka taurin kai fasali na, alal misali, kututturan itace.
Ina fatan wannan bayanin ya kasance da amfani gare ku, kuma za ku iya ƙarin koyo game da ƙwayoyin prokaryotic da eukaryotic.