- Porocytes: These are tubular cells that form the ostia.
- Amoebocytes: These are totipotent cells that can form other types of cells. They are named so because of their amoeboid movement throughout the mesohyl.
- Cells formed by amoebocytes are as follows:
- Trophocytes or nurse cells: provide food to developing cells
- Thesocytes: store food granules
- Collencytes: secrete collagen fibres and form connective tissue
- Chromocytes: pigmented cells
- Gland cells: secrete slimy substance
- Germ cell: produce ova and sperm
- Myocytes: help in closing and opening of osculum
- Scleroblasts: secrete spicules. These can be Calcoblast (calcareous spicules) and Silicoblast (siliceous spicules).
- Spongioblasts: secrete spongin fibres of mesohyl layer
-
-
The innermost layer called the inner epithelium or choanoderm. It is made up of choanocytes or collar cells. These cells trap and digest the food particles coming in through the water current via the ostia.
View full answer