Izitshalo zeSpermatophyte yilezo ezikhula kusuka embewini. Iqembu lezitshalo eliguquke kakhulu futhi lihlukaniswe laba izingxenye ezimbili: ama-angiosperms kanye ne ukuzivocavoca. Yize okwangaphambili kuyiwona ophethe kakhulu, ama-gymnosperms anelukuluku lokwazi kakhulu futhi anezici ezingavamile.
Ngakho-ke, sizonikezela le ndatshana ukukutshela zonke izici, ukuziphendukela kwemvelo kanye nokufuna ukwazi ngama-gymnosperms.
Izici eziyinhloko
Lezi yizitshalo zemithambo spermatophytes ekhiqizwa ngembewu. Bona uqobo lwabo bakhiqiza imbewu abazothuthukisa kuyo kamuva. NgesiGreki igama lama-gymnosperms lisinikeza umkhondo wazo zonke izici abanazo. Futhi kusho imbewu engenalutho. Lokhu kusenza sivele sazi ukuthi imbewu yayo inqunu ngokuphelele futhi ayikhuli esibelethweni esivaliwe.
Leli qembu lezitshalo lithuthuka kuzo zonke izindawo zomhlaba, yize ikakhulu sizibona ezindaweni ezibandayo nezisemakhazeni. E-taiga singabona inani elikhulu lama-gymnosperms akwazile ukuzivumelanisa nezimo ezishisayo zokushisa nemvula ngesimo seqhwa. Ezinye zazo zisetshenziswa njengezitshalo zokuhlobisa ngabantu noma ukukhiqizwa kwezinkuni. Lezi zitshalo zinezinkuni ezisezingeni eliphakeme. Yini enye, ama-gymnosperms yizitshalo ezinobukhulu obukhulu nempilo ende. Lezi yizici ezihlukanisa ngokusobala kwezinye izinhlobo zezitshalo.
Ake sihlaziye ngokujula kancane ukuthi ayini amandla ayo.
Amaphuzu avelele we-Gymnosperms
Isici esiyinhloko ukukhiqizwa kwembewu engakhuli ngaphakathi kwe-ovary. Ngaphezu kwalokho, zonke ziyizitshalo ezikhula ngaphandle kwezimbali noma izithelo. Kodwa-ke, imbali yayo ingacatshangwa njengegatsha lokukhula okulinganiselwe okwakha izigaxa noma izigaxa. Amanye awo akhiqiza amaqabunga avundile, awaziwa nangokuthi ama-sporophylls, anembewu eveziwe. Ubulili balezi zitshalo buhlukanisiwe njengoba kukhona izigaxa zesifazane ezikhiqiza ama-ovules nezigaxa zesilisa ezikhiqiza impova.
Uma sibuyela emuva ekubuyeni kwazo zonke izitshalo kuwo wonke umlando weplanethi yoMhlaba siyabona ukuthi ziyizitshalo zasendulo kakhulu. Eqinisweni, baba ngabokuqala ukuba izitshalo zasemhlabeni bakhiqiza imbewu. Umsuka wayo usukela ekupheleni kwesikhathi seCarboniferous. Lokhu kungenzeka ngoba ukukhiqizwa kabusha kwalezi zitshalo ukukhulisa indawo yazo yokwabiwa kungenziwa ngaphandle kwamanzi. Futhi ingabe iningi lazo lipholile ngenxa yomoya. Futhi banokumelana okuphezulu nezimo zezulu ezingezinhle njengamazinga okushisa kakhulu nemvula enjengeqhwa.
Mayelana nokubukeka nokwakheka kwayo, yizitshalo ezinamapulangwe ezinokubukeka kwezidumbu. Iningi lazo linezimpande, iziqu, amaqabunga kanye nembewu. Inezicubu zemithambo ezivumela ukuba zisabalalise amanzi nezinye izinsiza kusuka ezimpandeni kuya emaqabungeni. Ngenxa yale migudu yemithambo yegazi bangondla izakhi ezisenhlabathini. Ngaphezu kwalokho, bangagcina amandla futhi bathole izakhamzimba eziningi nge-photosynthesis.
Ukukhiqizwa kabusha kwama-gymnosperms
Njengoba sishilo ngaphambili, kunezitshalo ezinezigaxa zesilisa nezinye, njengezesifazane. Lezi zibopho zesilisa zenziwa ngesikali namasaka amabili empova akha izinhlamvu zempova. Izigaxa zesifazane zinkulu futhi ziqukethe kuphela isikali esinama-ovules amabili. Kungashiwo ukuthi ama-gametes yizinhlamvu zempova ezibhekele ukufaka umquba kuma-ovules.
Ngesikhathi sokukhiqizwa kabusha kwalezi zitshalo, umoya uphethe ukuhambisa izinhlamvu zempova ezimbalini zezinsikazi. Kumele kuqashelwe ukuthi ama-gymnosperms enza inani elikhulu lokungezwani komzimba nabantu. Phakathi nenkathi yokuzalanisa, umoya ususa okusanhlamvu kwempova futhi khiqiza ukungezwani komzimba nabantu abaningi abanamasosha omzimba asengozini. Lapho umoya usuhambise okusanhlamvu kwe-pollen kuya ezimbali zezinsikazi futhi ishubhu le-pollen lingena esibelethweni, linikeza i-zygote ngemuva kokuhlangana kwama-gametes.
Ngemuva kokukhulelwa, imbewu iyakhiwa bese kuthi i-inflorescence yesifazane iguquke ibe uphayinaphu okuthi, ngemuva kwesikhashana, ivulekele ukukhipha imbewu. Lezi zinhlamvu zinesibopho sokwakha izitshalo ezintsha lapho ziwela phansi.
Izibonelo
Sizobona ezinye zezibonelo eziyinhloko zezitshalo ze-gymnosperm, ngoba kunezinhlobo ezingaphezu kwenkulungwane ezihlukaniswe izizukulwane ezingama-88. Eminye yaziwa njenge-firs, pines, cypresses, junipers, cedars and araucarias, yize ezinye zingaziwa kangako. Ezinye izibonelo yilezi ezilandelayo:
Izitshalo zeqembu lama-pinophytes yilezo ezaziwa ngokuthi ama-conifers. Kunezinhlobo ezingaphezu kuka-600 zezitshalo futhi zonke zinokhuni. Kunezihlahla eziluhlaza njalo njalo. Iningi lazo linamaqabunga afana nenaliti ukuze lisinde kangcono esimweni sezulu esibi.
- Eqenjini lamaPináceas sinezihlahla zikaphayini, ama-firs, imisedari, izibungu noma ama-tsugas.
- I-Cupresáceas ingumjunipha, imisipresi nama-sequoia.
- ETaxáceas sineyew
- Ama-Aracauriáceas
- EPodocarpáceas kukhona i-lleuque noma i-mañío.
Ama-Ginkgophites afaka izinhlobo eziningana ezingasekho futhi eyodwa kuphela ephilayo. Zivame ukubhekwa njengezinsalela eziphilayo futhi okuwukuphela kohlobo olukhona yi Ginkgo biloba. Ama-cycads elinye iqembu lama-gymnosperms okubukeka kwawo kufana nemithi yesundu. Okokugcina, ama-gnetophites akha imivini nezihlahlana ezincane ezineziqu ezimfishane namaqabunga anezikhala.
Umehluko phakathi kwama-gymnosperms nama-angiosperms
Phambilini sishilo ukuthi lezi zitshalo ezimbili yizona ezivele kakhulu embusweni wezitshalo. Zombili ziyizitshalo zemithambo ye-spermatophyte ezikhiqiza imbewu. Kodwa-ke, kukhona umehluko oqinile phakathi komunye wabo:
- Ama-Angiosperms anembewu ezungezwe izithelo, kuyilapho ama-gymnosperms eyimbewu engenalutho.
- Ama-Gymnosperms azinazo izimbali ezijwayelekilekunalokho, ngokuvamile banezigaxa.
- Amaqabunga ama-angiosperms ngokuvamile ayisicaba, kuyilapho ama-gymnosperms Ziyinaliti ukuze zikwazi ukuzivumelanisa nezimo zezulu ezingezinhle.
- Ama-Angiosperms ayizitshalo zonyaka, kuyilapho ama-gymnosperms ehlala iningi lawo.
Ngiyethemba ukuthi ngalolu lwazi ungafunda kabanzi ngezitshalo ze-gymnosperm kanye nezici zazo.