Question

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Q: What is the difference in the formation of the body of Porifera and the bodies of all other Phyla?

Answer 1

porifera includes sponges.its organization is of cellular grade.sponges doesnot contain any components that can be considered as organs/parts

sponges do not have stomaach sac,renal components(kideneys),instead sponge cells of various types are modified for bodily functions which acts as body organs.

choanocytes-lines interior body walls of sponges.

cells consists of central flagellum that is encircled by a collar of microvilli.

these are versatile cells.their flagellla strike to create the active pumping of water through,and the collars of the choanocyte are the primary areas that nutrients are absorbed in to sponge.

suprisingly in some sponges the choronoflagellates develop in to gametes.

Mesohyl- in junction of two layers is a small space called mesohyl,it has matrix which is made of protein.

Aracheocytes-

These are totipotent cells ,they can change to any other type of cell.choanocytes caughts food and they send to ingest and digest by aracheocytes and transport nutrients to other cells.

Sclerocytes-

sclerocytes secrets spicules.

skin cells-

these are pinacocytes ,present in outside of sponge wall.

Myocytes-

sponges donot have muscle spindle cells,so thier locomotion is finitee.

canal openings pores sorrounded by myocytes and they can contract to control flow through sponge.

All phyla comes on casual side but porifera comes in another side by modification in cellular changes.