How many years does it take for an amount of water equal to the entire volume of the ocean to cycle through hydrothermal vents?

W)1000 years

X) 100,000 years

Y) 10 million years

Z) 1 billion years

Answer: Y

Why are chelators important to marine organisms?

W) They absorb sunlight

X) They bind trace metals

Y) They prevent sinking

Z) They enhance feeding

Answer: X

What environmentally harmful isotope was produced during the 1954 'Bravo' thermonuclear detonation at Bikini Atoll?

W)Uranium 238

X) Nitrogen-15

Y) Cesium 137

Z) Carbon14

Answer: Y

Which two molecules increase in concentration in deep water as it travels from the North Atlantic to the North Pacific ocean?

W)Oxygen and nitrate

X) Nitrate and carbon dioxide

Y) Oxygen and carbon dioxide

Z) Carbon dioxide and carbon-14

Answer: X