Why do sclown fish and sea anemone pair up? What is this relationship called?

The "clown fish" lives among the tentacles of sea anemone. What is this interaction between them called and why?

What do we get from sea water?

Why do we call our heart myogenic?

Why is the mode of conduction of electrical impulse along the myelinated neurons advantageous to a non-myelinated neuron? What is this type of conduction called?

What are noble gas elements ? Why are they so called?