Notes Ghar

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 Classification of the subclass : Apterygota                         Upto Orders                                         Page -1 Page -2 Page -3 Page -4 Page -5

 Coelom is one of the characteristic features of metazoans. The true coelom is a body cavity formed during embryo development from the three germinal layers. The body cavity meaning a fluid filled space that can accomodate organs. The coelom is lined by mesodermal epithelium cells. Presence or absence of coelom is one of the criteria for classifying animals.                                      Fig :- coelom Animal Kingdom:-  1. Acoelomate(no coelom)     Ex:-Porifera ; Coelenterata ; Ctenophora; Platyhelminthes 2. Pseudocoelomate(false coelom)          Ex :- Aschelminthes 3. Coelomate(true coelom)            Ex :- Annelida ; Arthropoda ; Mollusca ; Echinodermata ;Hemichordata ;Chordata Coelom Definition  “The coelom is the fluid-filled body cavity present between the alimentary canal and the body wall.” The true coelom has a mesodermal origin. It is lined by mesoderm. The peritoneal cavity present in the abdomen and similar spaces around other organs such as lungs, heart are parts of t