Cov ceg ntawm biology uas cuam tshuam nrog kev kawm txog tsiaj cov kab mob uas nyob hauv lub ntiaj teb hu ua zoology. Ib qho ntawm nws cov ntu ncaj qha txiav txim siab txog ib pawg ntawm cov tsiaj txhu - crustaceans. Lawv cov qauv, cov yam ntxwv ntawm lub neej, nrog rau qhov tseem ceeb ntawm crustaceans hauv qhov xwm txheej thiab tib neeg lub neej yuav tau tham hauv kab lus no.
Crustacean taxonomy
Ntawm cov kab mob invertebrate inhabiting peb ntiaj chaw, tsiaj sawv tawm, uas tau ua ke rau hauv hom Arthropods. Crustaceans yog ib qho ntawm cov superclasses ntawm no taxon, uas nws cov neeg sawv cev nyob hauv cov dej tshiab los yog dej hiav txwv. Tsuas yog ob peb tug ntawm lawv, xws li cov nas tsuag ntoo thiab av crabs, nyob hauv thaj chaw ntub dej. Superclass Crustacea suav nrog: chav kawm ntawm qis crayfish thiab chav kawm siab dua (decapod) crayfish.
Thiab, txhua tus ntawm cov se no muaj cov pab pawg me me - xaj. Lower crustaceans ua lub hauv paus ntawm zooplankton, yog li lawv muaj qhov tseem ceebqhov tseem ceeb nyob rau hauv ntuj thiab tib neeg lub neej. Hauv cov ntsiab lus, ua ib qho ntawm thawj qhov sib txuas hauv cov khoom noj khoom haus, qis crayfish yog cov khoom noj rau cov ntses thiab cov tsiaj hauv dej. Ua tsaug rau cov neeg sawv cev ntawm qhov kev txiav txim ntawm isopods, copepods thiab cladocerans, marine lub neej tau txais cov khoom noj muaj protein ntau, vim lub cev ntawm cov crayfish qis suav nrog cov polypeptides yooj yim digestible.
Cov chav kawm ntawm cov crustaceans siab dua suav nrog ib qho kev txiav txim - decapod crayfish, uas yog sawv cev los ntawm cov tsiaj xws li crabs, lobsters, lobsters thiab cw.
Tus yam ntxwv ntawm cov qauv ntawm crustaceans
Kev faib tsiaj rau hauv cov chav kawm yog nyob ntawm qhov sib txawv ntawm cov qauv sab nraud ntawm cov kab mob no. Nyob rau hauv qis crayfish, xws li cyclops (ib tug detachment ntawm copepods), daphnia (ib tug detachment ntawm cladocerans), cov ntshauv ntoo (ib tug detachment ntawm isopods), lub cev muaj ib tug sib txawv tus naj npawb ntawm ntu (segments), thiab tsis muaj ceg ntawm ceg. plab. Ntawm nws qhov kawg ntu muaj kev tsim tshwj xeeb - rab rawg. Lub cev nws tus kheej muaj cov mos mos thiab nyias chitinous plhaub los ntawm cov khoom nruab nrog cev ntawm cov tsiaj pom.
Cov crustaceans siab dua, uas nws cov neeg sawv cev muaj lub plhaub tawv chitinous impregnated nrog txiv qaub, kuj txawv los ntawm kev faib tawm nruj ntawm lub cev rau hauv cephalothorax thiab lub plab nrog rau cov ntu tas li hauv lawv. Yog li, crayfish muaj 5 thiab 8 ntu hauv cheeb tsam cephalothoracic, feem, thiab lub plab muaj 6 ntu. Tsis tas li ntawd, tus crayfish siab dua, tsis zoo li cov qis dua, muaj ob txhais ceg ua luam dej ntawm lub plab.
Metabolism thiab kev ua haujlwm tseem ceeb
Raws li tau hais dhau los,Lub neej ntawm crustaceans tshwm sim hauv dej. Yog li ntawd, lawv qhia meej txog qhov hu ua idioadaptations - hloov mus rau ib qho chaw tshwj xeeb: ua pa nrog tag nrho lub cev ntawm lub cev los yog gills, lub cev zoo nkauj, lub plhaub uas muaj chitin thiab impregnated nrog cov tshuaj tiv thaiv dej - calcium carbonate.
Crustacean systems, xws li circulatory, ua pa thiab excretory, muab homeostasis - tswj ib tug ib txwm theem ntawm metabolism. Nws yuav tsum tau muab sau tseg tias tag nrho cov crustaceans muaj ib tug qhib circulatory system, thiab lub plawv zoo li ib tug pentagonal sac-zoo li lub cev nrog 3 khub li qub. Los ntawm nws mus rau cephalothorax thiab plab, cov hlab ntsha tawm mus, los ntawm cov ntshav nqa cov as-ham thiab oxygen mus rau tag nrho cov kabmob ntawm tus tsiaj, nchuav rau hauv lub cev sib xyaw ua ke hu ua mixocoel. Los ntawm nws, cov ntshav venous twb nkag mus rau hauv cov gills, qhov twg nws tawm los ntawm carbon dioxide thiab saturated nrog oxygen, tig mus rau hauv cov hlab ntsha. Los ntawm qhov nyob rau hauv lub pericardial sac, nws nkag ncaj qha mus rau hauv lub plawv.
Shitni - ib pawg peculiar ntawm crustaceans
Cov tsiaj no, uas yog ib pab pawg neeg nyob hauv dej tshiab, tuaj yeem nyob hauv dej qhuav. Thaum cov dej evaporates, daim ntaub thaiv nws tus kheej yog faus rau hauv av thiab tsis poob nws txoj kev vam meej rau ib lub sijhawm. Cov qe tso los ntawm tus poj niam rau hauv qab ntawm lub pas dej tauv ntev txog 15 xyoos. Lawv tau yooj yim nqa los ntawm cua nrog rau cov av, yog li shieldworms nyob yuav luag txhua qhov chaw tshwj tsis yog Antarctica thiab African suab puam.
Crustacean life cycle
Cov neeg sawv cev ntawm lub superclass no muaj ob qho tib si nws cov qauv yooj yim, piv txwv li, kev txhim kho ncaj qha ntawm crayfish, thiab ntau qhov nyuaj, suav nrog cov theem larval. Hauv qhov no, txoj kev loj hlob yog hu ua indirect. Nws yog tus yam ntxwv ntawm kev txiav txim ntawm copepods thiab cladocerans, thiab tseem muaj nyob rau hauv cov crayfish siab dua, piv txwv li, lobsters lossis spiny lobsters. Crustaceans, uas nws cov neeg sawv cev muaj pelagic los yog planktonic daim ntawv ntawm larvae, lub thiaj li hu ua nauplii thiab zoea, yog dav nyob rau hauv cov xwm: lawv yog cov neeg nyob ntawm ntug dej hiav txwv ntawm Australia, North America, thiab Europe. Txhua theem ntawm lub neej voj voog ntawm crustaceans yog tswj los ntawm lawv cov endocrine system, sawv cev los ntawm androgenic, postcommissural thiab sinus qog. Lawv tso cov tshuaj hormones uas tswj cov txheej txheem ntawm kev puberty, molting, thiab kev hloov ntawm larvae mus rau cov neeg laus.
Qhov tseem ceeb ntawm crustaceans hauv xwm thiab tib neeg lub neej
Tsiaj txhu muaj nyob rau hauv qhov kev txiav txim ntawm decapods, xws li lobsters (lobsters), lobsters, crabs, yog cov khoom lag luam muaj txiaj ntsig uas muab tib neeg cov nqaij qab thiab cov protein ntau. Cov neeg sawv cev ntawm cov crayfish qis yog qhov tseem ceeb heev: cyclops, daphnia, dej luav, uas yog zaub mov rau ntses, piv txwv li, xws li cov ntses salmon thiab sturgeon.
River crayfish, feem ntau hu ua orderlies, ntxuav hauv qab ntawm cov organic teeb meem tuag. Txawm hais tias qhov tseem ceeb ntawm crustaceans hauv qhov xwm txheej thiab tib neeg lub neej yog qhov zoo, tab sis qee cov tsiaj muaj kev phom sij, piv txwv li,carp ntsha ua rau loj tuag ntawm kev lag luam hom ntses. Thiab cyclops yog nruab nrab ntawm cov kab mob cab: guinea worms thiab wide tapeworm.
Peb ntseeg tau tias cov tsiaj no, uas yog ib feem ntawm Arthropoda phylum, yog qhov txuas tseem ceeb hauv lub ntiaj teb ecosystems ntawm peb lub ntiaj teb thiab qhov tseem ceeb ntawm crustaceans nyob rau hauv cov xwm thiab tib neeg lub neej yuav tsum tsis txhob underestimated. Qee hom ntawm cov tsiaj no (piv txwv li, broad-toed crayfish, mantis cw) tau teev nyob rau hauv Phau Ntawv Liab, thiab lawv txoj kev puas tsuaj raug rau txim.
