Muscle tissues signaling muscle tissues to contract.
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).
Answer:
Marine mining is a process that can be done by dredging the seabed and is used for the extraction of mineral resources from the seabed, which are non-renewable, with a negative impact on marine ecosystems.
Explanation:
The illustration shows a process of marine mining by dredging, where the resource extracted is of a mineral nature, like copper, zinc, silver and gold. Gravel used for construction can also be extracted from the sea. Mineral resources extracted from the sea are not renewable.
The process of marine mining can be harmful to the ecosystems there, so it must be a process that requires control and management from the ecological point of view.
Two possible consequences of not regulating marine mining are:
- <u><em>Destruction of the habitat of life forms present on the sea floor</em></u><em>, which endangers many species and even forces migration to more stable areas, with consequences on the food chains.
</em>
- <em><u>Extinction of marine species that inhabit the seabed</u></em><em>. The flora and fauna of the sea floor usually have slow reproductive cycles and, in the case of fish, spawning takes place on the bottom of the sea. Mining endangers the reproductive cycles of the species, leading to induced extinction.</em>
Responsible and controlled mining activity can be useful for humans, while avoiding negative consequences on the ecosystems that exist at the seabed.