Members of phylum Porifera are commonly known as spongs. They are generally marine and mostly asymmetrical animals. These are primitive multicellular animals and have cellular level of organization (lacks tissues). These Organisms (belonging to phylum Porifera) lacks most of the structures that are present in multicellular organisms like digestive system, respiratory system, Brain etc
Body of Spongs are made up of spicules or spongin fibers and these organism contain a water canal system which helps them in digestion, reproduction and catching their food in marine habitat.
Answer:
Please list the statements there are to choose from, this way, even people outside your school and/or grade level will be able to answer your question.
Explanation:
<span>the stratum lucidum is an epidermal layer. It is a clear layer of dead skin cells. Even under a microscope it is not visible, only under a light microscope can it be viewed. It is only found on the palms of ones hands and the soles of the feet.</span>
The correct answer is - nitrogen and phosphorus.
The nitrogen and the phosphorus are the two substances that cause most of the eutrophication. It is good for the organisms that live in the water when these two substances are available as they are very important nutrients, but if the optimal amount is surpassed than it can be devastating. When there's high quantities of nitrogen and phosphorus in the water it makes it much more rich in nutrients that it should be. That kind of situation is the best for the algae, which start growing all over the place, quickly covering the water and becoming the dominant life form. As that happens, the organisms that use photosynthesis will die out because the Sun will be blocked, and the algae will also contribute to a big reduction of the oxygen in the water too. The end result being totally destroyed ecosystem that has been overtaken by algae.
