Sea urchins are preyed about by many predators that inhabit their marine environment, but also those animals that don't. The main predators of the sea urchin are crabs, large fish, sea otters, eels, birds and humans.
Interphase is the phase during which the growth of the cells take place along with the metabolic activity but the nuclear division in the cell does not occur. The three stages included within the interphase are the G1, S and G2.
1 Adenosine Triphosphate (ATP) : a nucleotide composed of adenine, the sugar ribose, and three phosphate groups; involved in energy metabolism and required for RNA synthesis. 2  It exists in cells in a form of high-energy phosphate bond to store and transport chemical energy.