What is an echinoderm with long spines?

The echinoderm with long spines belongs to the class Echinoidea which includes sea urchins, heart urchins, cake urchins and sand dollars. This spine serves as their protective mechanism from predators. The spines are joined to the skeleton and muscles surround it. The muscles enable them to swivel its spines from predators.

[ answer ]

foliated

[ explanation ]

foliation forms in a rock when pressure squeezes the rock together. the rock then has a design of many different color little lines. there are three types of foliated rock. the types are slate, schist, and gneiss. each type of foliated rock is different based on grain size and foliation characteristics. the lines appear when the rock has been under pressure.

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step 1 ammonium can be absorbed by plants, but some is converted into nitrates which are better for plants to absorb. this is called nitrification. 2. step 2 the deer eats the plants and uses the nitrogen-containing proteins for cell growth. 3. step 3 bacteria in the soil conduct nitrogen fixation to convert nitrogen gas from the atmosphere into ammonium. 4. step 4 some of the nitrates are absorbed back into plants, but denitrification breaks down the nitrates into nitrogen gas released back into the atmosphere. 5. step 5 nitrogen is found in the urine, which gets broken down into ammonium through the process of ammonification. 6. step 6 plants absorb the ammonium and begin assimilation, the process to add the nitrogen to protein.