mesohyl
Quick Summary
The mesohyl is an amorphous, gelatinous substance found in sponges that contains various cells, fibers, and skeletal elements. It is not a definite organ but rather a matrix that supports the sponge's structure and functions.1
Key components within the mesohyl include:
* Cells: Archaeocytes, which are amoeboid and can transform into other cell types, play roles in regeneration, food transport, and potentially reproduction. Collencytes secrete fibers, while sclerocytes produce skeletal spicules.21
* Skeletal elements: Sponges can have mineral skeletons made of calcium carbonate or silica in the form of spicules, or they can be composed of spongin, a proteinaceous material. Some sponges lack skeletons entirely.34
* Function: The mesohyl facilitates the movement of water through the sponge's canal system, which is crucial for bringing in food and oxygen, and for removing waste products. It also houses specialized cells that contribute to the sponge's skeleton and defense.541
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- spongeSexual reproduction
…in the amorphous substance (mesohyl) that fills the sponge. In the amphiblastula, the choanocytes are derived from the forward flagellated region; the other cells and the mesohyl are derived from the posterior half. Choanocytes create the water currents through sponges and capture food particles.
Read More…in the amorphous substance (mesohyl) that fills the sponge. In the amphiblastula, the choanocytes are derived from the forward flagellated region; the other cells and the mesohyl are derived from the posterior half. Choanocytes create the water currents through sponges and capture food particles.
Read More - spongeOxygen uptake and excretion
Special amoebocytes disintegrate in the mesohyl, and their granules are expelled through the canals. The excretory products of the sponges—ammonia and other nitrogen-containing substances—account for their characteristic unpleasant odour. Many sponges (e.g., the tropical sponge Tedania ignis) exude large quantities of mucus, and some species produce toxic substances, which may…
Read MoreSpecial amoebocytes disintegrate in the mesohyl, and their granules are expelled through the canals. The excretory products of the sponges—ammonia and other nitrogen-containing substances—account for their characteristic unpleasant odour. Many sponges (e.g., the tropical sponge Tedania ignis) exude large quantities of mucus, and some species produce toxic substances, which may…
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