Sponges: aquatic life invertebrates
What they are and examples
Spongers are invertebrate animals of aquatic life, with most species living in saltwater. They are also called porifers. Examples of these animals are the approximately twelve thousand species of marine sponges in the world.
Main features of spongers anatomy:
- The digestion of sponges is intracellular (inside the cell) and performed by coanocytes, which perform phagocytosis through the diffusion process.
- They have no circulatory system. The food is carried by the amoebocytes.
- Reproduction can be of two types: asexual (by budding and budding) and sexual (hair ciliary production).
- They have no respiratory system. Respiratory changes are performed individually by each cell through the diffusion system.
- Excretion is done by each cell through diffusion.
- Sponges have no nervous system or muscles.
- Water in and out of a sponge is performed by the myocytes, which control the pore opening.
- The integumentary system consists of a layer of pinacocytes (flat-shaped cells).
- Spongers have external skeleton. This can be composed of spongine fibers or crystalline spicules (calcium carbonate or silica).
- There are some species of sponges that live in the sea at a depth of 5,000 meters.
- Marine biologists have already identified some species of sponges that are carnivorous.