Ba a saba samun kalmar "kashi na membrane" a cikin ƙamus a matsayin shigarwa daban, amma kalma ce da ake amfani da ita a cikin jiki don kwatanta nau'in kashi da ke tasowa daga nama mai gaɓoɓi, sabanin samfurin cartilaginous. p>A cikin ci gaban amfrayo, kasusuwa na iya samuwa ko dai ta hanyar endochondral ossification, inda suke tasowa daga samfurin guringuntsi, ko kuma ta hanyar ossification na ciki, inda suke samuwa kai tsaye daga nama mai ciki. , irin su wadanda ke cikin kwanyar, kuma an samo su ta hanyar bambance-bambance da kuma ma'adinai na kwayoyin halitta na mesenchymal a cikin membrane mai haɗawa. Waɗannan ƙasusuwan sun kasance masu sirara kuma suna da ɗan haske, amma suna da ƙarfi, kuma suna da mahimmanci don kare mahimman gabobin kamar kwakwalwa.