Qhov sib txawv tseem ceeb ntawm cov placoid thiab cov nplai cycloid yog cov nplai placoid yog cov duab peb sab, cov qauv ntxhib tam sim no hauv cov ntses cartilaginous, thaum cov nplais cycloid yog puag ncig, cov qauv hloov pauv tam sim no hauv cov ntses pob txha.
Cov exoskeletal npog ntawm vertebrates yog ua los ntawm ob hom teev. Lawv yog cov epidermal thiab dermal. Epidermal nplai yog tsim tau zoo nyob rau hauv vertebrates xws li cov tsiaj reptiles, noog, thiab tsiaj txhu, thaum dermal scales yog zoo tsim nyob rau hauv cov ntses. Placoid nplai thiab cycloid nplai yog ob hom dermal nplai. Lawv ua raws li cov qauv tiv thaiv tawm tsam cov tsiaj qus.
Placoid Scales yog dab tsi?
Placoid nplai yog me me, daim duab peb sab, zoo li cov hniav uas npog daim tawv nqaij ntawm cov ntses cartilaginous. Placoid scales tsis loj hlob tom qab ib tug kab mob mus txog tag nrho cov maturity. Placoid nplai muaj cov duab plaub lub hauv paus uas tau muab tso rau hauv cov tawv nqaij ntses. Lawv kuj hu ua dermal denticles vim lawv loj hlob tawm ntawm dermis txheej ntawm cov kab mob. Ib yam li cov hniav, lawv muaj lub hauv paus, uas muaj cov ntaub so ntswg, cov hlab ntsha, thiab cov hlab ntsha. Lub pulp kab noj hniav yog nourished los ntawm ib txheej ntawm odontoblasts, uas secrete dentine. Dentine yog cov khoom siv calcified, thiab nws tsim lwm txheej ntawm cov nplai. Cov no haum nruab nrab ntawm cov nplais qub tsim ua ntej. Lub dentine yog coated nrog cov khoom zoo li enamel hu ua vitrodentine. Vitrodentine nyuaj dua li dentine thiab tsim nyob rau hauv ectoderm.
Daim duab 01: Placoid Scales
Placoid nplai feem ntau yog ntim nruj ua ke. Lawv loj hlob tig rov qab thiab nteg ncaj rau ntawm daim tawv nqaij. Placoid nplai yog ntxhib, thiab cov qauv tsis tuaj yeem nkag mus. Cov nplai no tiv thaiv ntses los ntawm cov tsiaj nyeg. Daim duab peb sab yuav txo qis thiab ua rau muaj kev kub ntxhov thaum ua luam dej.
Cycloid Scales yog dab tsi?
Cycloid scales yog du-edged, cov qauv sib xws uas npog daim tawv nqaij ntawm cov ntses pob txha. Cov nplai no muaj ob thaj chaw. Cov txheej hauv fibrous yog tsim los ntawm collagen, thaum txheej txheej pob txha yog calcium-based thav duab. Ntawm qhov txias txias, cov nplais cycloid zoo li loj hlob ze thiab maj mam, tawm hauv qhov tsaus nti hu ua lub annulus.
Daim duab 02: Cycloid Scales
Cycloid nplai feem ntau pom muaj nyob hauv cov ntses siab, thiab lawv muab kev tiv thaiv sab nraud rau lub cev. Lawv hloov tau yooj yim thiab muaj ib puag ncig cov qauv. Lawv yog thicker nyob rau hauv nruab nrab vim collagen yog tam sim no. Ib feem ntawm cov nplai uas raug rau thaj tsam tom qab qhia tau tias tsawg dua ridges, thiab thaj tsam sab hauv yog kos rau ntawm daim tawv nqaij. Cycloid scale yog cov nplai sib tshooj thiab muaj cov nplhaib loj hlob. Cov nplai no txuas ntxiv mus ntxiv thaum cov ntses loj tuaj. Qhov no ua rau tus qauv ntawm kev loj hlob ntawm cov nplhaib ntawm qhov ntsuas.
Dab tsi zoo sib xws ntawm Placoid thiab Cycloid Scales?
- Placoid thiab cycloid nplai pom hauv ntses.
- Lawv muab kev tiv thaiv sab nraud.
- Ob leeg yog cov nplais tawv nqaij.
Qhov txawv ntawm Placoid thiab Cycloid Scales yog dab tsi?
Placoid nplai yog daim duab peb sab, cov qauv ntxhib tam sim no hauv cov ntses cartilaginous, thaum cov nplai cycloid yog puag ncig, cov qauv hloov pauv tam sim no hauv cov ntses pob txha. Yog li, qhov no yog qhov sib txawv tseem ceeb ntawm placoid thiab cycloid nplai. Ntxiv mus, placoid scales nres loj hlob ib zaug cov ntses loj hlob nrog lub sij hawm, tab sis cycloid nplai loj hlob nrog kev loj hlob ntawm cov ntses. Tsis tas li ntawd, cov nplai placoid yog cov nplais nruj, tsis zoo li cov nplai cycloid.
Cov hauv qab no qhia txog qhov sib txawv ntawm cov placoid thiab cycloid nplai nyob rau hauv daim ntawv tabular rau ib sab ntawm kev sib piv.
Summary – Placoid vs Cycloid Scales
Placoid thiab cycloid nplai muaj nyob hauv cov ntses, thiab lawv muab kev tiv thaiv sab nraud tiv thaiv cov tsiaj nyeg. Placoid nplai muaj qhov tshwj xeeb ntawm qhov tsis loj hlob tom qab lub cev loj hlob tag nrho, thaum cov nplai cycloid loj hlob nrog rau kev loj hlob ntawm cov kab mob, ua rau kev loj hlob rings. Cov qauv tawv ntawm cov nplai placoid yog tshwm sim los ntawm qhov muaj cov tshuaj calcified hu ua dentine. Placoid nplai feem ntau muaj nyob rau hauv cov ntses cartilaginous, thaum cov nplai cycloid muaj nyob hauv cov ntses pob txha. Yog li, qhov no qhia txog qhov sib txawv ntawm placoid thiab cycloid nplai.
