Why is the movement of Earth's Tectonic Plates significant?

The Earth's Tectonic Plates move when rising and falling convection currents cause pressure differentiates between the mantle and lithosphere. In your own words why is this movement important?

Affects of Water Composition on Fish

Just like with humans, nutrients in water affect the lives and health of fish. In order to provide more stable and healthy fish at fish farms, what nutrients do you think are most beneficial to add to the water and why?

Nitrogen In Our Air

The air we breath is (by volume) roughly 78.09% nitrogen, 20.95% oxygen, 0.93% argon, 0.039% carbon dioxide, with small amounts of other gases. Why do you think that nitrogen is such a large component of our atmosphere? How do you think this amount of nitrogen affects our bodies?