Sponges are similar to other animals in that they are multicellular, heterotrophic, lack cell walls and produce sperm cells. Unlike other animals, they lack true tissues and organs, and have no body symmetry.
The shapes of their bodies are adapted for maximal efficiency of water
flow through the central cavity, where it deposits nutrients, and leaves
through a hole called the osculum. Many sponges have internal skeletons of spongin and/or spicules of calcium carbonate or silicon dioxide. All sponges are sessile
aquatic animals. Although there are freshwater species, the great
majority are marine (salt water) species, ranging from tidal zones to
depths exceeding 8,800 m (5.5 mi).
<span>The ecosystem is the lowest level of the biosphere hierarchy to include weather patterns and soil conditions.
in the whole biosphere hierarchy, ecosystem actually placed as the second highest (1 place below biosphere)
But there are only 2 hierarchy that include weather and soils, and those hierarchies are biosphere and ecosystem. So technically the ecosystem will be the lowest in this matter</span>
Secondary succession because it was previously abandoned but since its been found theres a new ecosystem growing . ( u could word it a bit differently but it’s definitely secondary succession )