Los Yenyani (IiChondrichthyans), ekwabizwa ngokuba yi-cartilaginous fish, liqela lezilwanyana ezinomqolo zakudala kakhulu zasemanzini. Nangona bengebaninzi okanye bahluke njengeentlanzi zamathambo, ukuguquguquka kwe-morphological, ukuqubha kwezicubu zemisipha, amalungu oluvo, kunye nemikhwa enamandla yokuxhatshazwa kunye nemihlathi ibonisa ukuba banikwe isimo esiqinileyo se-ecological kwindawo abahlala kuyo.
Kweli nqaku siza kukuxelela yonke into ofuna ukuyazi malunga neChondrichthyes, iimpawu zabo kunye nebhayoloji.
Iimpawu eziphambili zeChondrichthyes
Kukho iintlobo ezimbini zeentlanzi ze-cartilaginous. Okulandelayo, siza kuchaza iimpawu zayo eziphambili:
Elasmobranchs
Ookrebe kunye nemitha yeli qela lezilwanyana. Ezinye zazo zizilwanyana ezidla inyama, zifumana ixhoba lazo ngamalungu azo anukayo ngenxa yokungaphuhlisi kakuhle kokubonakalayo. Okwangoku, kukho iintlobo ezingaphezu kwe-400 ze-shark kwii-odolo ze-8 kunye neentlobo ze-500 zemisebe kwii-4 imiyalelo. Ngokubhekiselele kookrebe, uninzi lunezi mpawu zilandelayo:
- Umzimba: Umzimba omile okwe-spindle onobuso obutsolo kunye nesisu ngaphambili. Umsila womzimba unomsila ovaliweyo ongaqhelekanga, oko kukuthi, kukho iimilo ezimbini ezahlukeneyo kunye nezakhiwo zamagqabi, enye yazo iqulethe isiphelo somqolo, kwaye ngaphambili inesibini samaphiko e-pectoral, iperi yamaphiko e-pelvic. , kunye nemiqolo emibini. amaphiko angaqhelekanga. Kwamadoda, amaphiko e-pelvic aye aguqulwa ngaphambili njengamalungu esini sokukhwelana kwaye abizwa ngokuba yi-glycoptera, i-pteropods, okanye i-genus.
- Umbono, ulusu kunye namalungu e-receptor: ngokumalunga nomlomo, zineempumlo ezifanayo, ze-ventral kunye nangaphambili. Amehlo awanazo iziciko, nangona ezinye iintlobo zineenwebu ze-nictitating, ezine-stoma emva kwenkophe nganye. Ulusu lomelele kwaye kwezinye iintlobo lufana nephepha lesandpaper, linamaxolo amile okwepleyiti, ekwabizwa ngokuba yidermal scales, acwangciswe ngendlela yokunciphisa ukudubadubeka nokujongana nomva. Bane-neuromas kuyo yonke imizimba yabo kunye neentloko, eziye zamkeleka kakhulu kwii-vibrations kunye nemisinga yamanzi. Kwakhona banama-receptors akhethekileyo angakwazi ukubona ixhoba ngokusebenzisa intsimi yombane abayikhuphayo, i-Lorenzini blisters entloko.
- Amazinyo: Amazinyo awadibanisi nomhlathi ongezantsi, kukho imiqolo emibini, umqolo wokugqibela uthatha indawo yamazinyo angekhoyo kumqolo wokuqala, ngoko ke amazinyo amatsha angahlala ekhula. Ngokuxhomekeke kwiintlobo, ezi zinokuba ne-serrated shape yokusika ukutya, zibukhali kwaye zibe nomsebenzi wokubamba, kwimeko yeentlobo ezinemizila, zinamazinyo angama-flat anokuthi akrwelwe phezu komhlaba.
- Amathambo Nokuqubha: Anamathambo ecartilage aneminerali, engenamathambo njengezinye iintlanzi. Kwakhona, abanaso isinyi sokuqubha, nto leyo ebangela ukuba bahlale bequbha okanye bahlale emazantsi, kungenjalo baya kutshona. Kwelinye icala, banesibindi esikhulu, esine-lipids (squalene), esisithintela ukuba singaziki.
IHolocephalos
Ngaphakathi kweChondrichthyes sifumana eli qela elibandakanya i-chimeras. Eli qela lincinane lenziwe malunga neentlobo ezingama-47 namhlanje. Ngokwe-anatomically inomxube we-elasmobranch kunye neempawu zentlanzi ezinamathambo:
- Umzimba: Zinemilo engaqhelekanga kakhulu, imizimba yazo yande kwaye iintloko zazo ziphumela ngaphandle, zinesakhiwo sakudala esikwaziyo ukuxhasa iimazi ngexesha lokukhwelana. Impumlo ifana nomvundla kwaye umsila wayo ufana nesabhokhwe.
- Imihlathi namazinyo: Azinamazinyo, kodwa zibanzi, iipleyiti ezisicaba. Umhlathi ongasentla udityaniswe ngokupheleleyo nokakayi, ngokungafaniyo neminye, kulapho igama lawo livela khona (holo = yonke, yonke kunye ne-cephalo = intloko).
- Ubungakanani: Zinokuba ziimitha ezi-2 ubude.
- U khuselo: Iphiko lalo lomqolo linomqolo onetyhefu.
- Ukutya: Ukutya kwabo kusekelwe kwi-crustaceans, i-mollusk, i-echinoderms, iintlanzi ezincinci kunye ne-algae, eziyimixube yokutya ezikugaya ngexesha lokutyisa.
Ukuqubha kweChondrichthyes
I-Elasmobranchs inezikali ze-dermal, ezivumela ukuba zinciphise i-turbulence xa iqubha. Kwelinye icala, kunye nesibindi sabo esine-lipid-rich, ukukwazi kwabo ukuginya umoya, kunye namaphiko abo, bangabaqubhi abagqwesileyo kwaye olu hlengahlengiso lubavumela ukuba bahlale emanzini. Amaphiko angaqhelekanga anokukwenza ujingi, kwanamaphiko anokulawula. Kwelinye icala, iphiko elingasemva linokulawula ukutyhala kwaye livelise amandla okunqumamisa ngenxa yokumila kwawo okungaqhelekanga.
Imitha yeManta iqhelaniswa nobomi phantsi kwamanzi, umzimba usicaba, unamaphiko afanayo avulekayo aze adibane nentloko, asebenze njengamaphiko xa equbha. Amazinyo azo athe tyaba, ayakwazi ukukrwela umphezulu kunye nokusila ukutya, okudla ngokuba ziicrustaceans, iimollusk kunye neentlanzi ezincinci.
Imisila yawo imile okwesabhokhwe, inomqolo omnye okanye ngaphezulu ekupheleni, odityaniswe namadlala anetyhefu eentlobo ezithile. Zikwanazo nezitho zombane kumacala omabini entloko zazo, ezinokuvelisa izothuso zombane kwaye zothuse amaxhoba okanye amarhamncwa.
Ukuveliswa kwakhona
Iintlanzi zeCartilaginous zinokuchumisa kwangaphakathi kunye neendlela ezahlukeneyo zokuzala esiza kuzibona ngezantsi:
- Oviparous: Babeka amaqanda azaliswe yi-yolk ngokukhawuleza emva kokukhulelwa. Ookrebe abaninzi kunye nemitha zibeka amaqanda kwingxowa yekeratinous. Iifilaments ezifana ne-tendril zenza ekupheleni kwengxowa, ezisetyenziselwa ukunamathela kwinto yokuqala eqinileyo abayibambayo. Iimbumba zinokubumba kwiinyanga ezi-6 ukuya kwiminyaka emi-2. Ngokuqhelekileyo le pateni iyenzeka kwiintlobo ezincinci, ze-benthic, ezinokubeka amaqanda angama-100.
- Viviparous: Baya kuphuhlisa i-placenta yokwenyani apho i-embryo inokutya kuyo. Le ndlela yokuvelisa ikhuthaze impumelelo yabo yendaleko kweli qela. Kwenzeka malunga ne-60% yeentlanzi ze-cartilaginous kunye neentlobo ezinkulu ezisebenzayo.
- Oviviparous: bagcina i-embryo kwityhubhu ye-fallopian ngexesha lophuhliso lwe-embryonic kwaye bondla kwi-yolk sac yayo de ibelwe. Emva koko, inika iimbumba ngeentlobo ezahlukeneyo zokutya, ezifana ne-lecithin, apho i-embryo idla kwi-yolk yeqanda; isondlo sezicubu, apho i-embryo enye okanye ngaphezulu zondliwa ngulwelo (isondlo sezicubu) eziveliswa yi-villi kwindawo engaphakathi yesibeleko. Kwelinye icala, kukho ii<em>ovules, oko kukuthi, iimbumba ezitya amaqanda aqhamileyo xa zisesibelekweni. Ekugqibeleni, kukho i-oleanders okanye i-cannibalism kwisibeleko.
Ndiyathemba ukuba ngolu lwazi unokufunda ngakumbi malunga neChondrichthyes kunye neempawu zabo.