How do diatoms affect global atmospheric CO2 levels?
a. As surface seawater warms, the photosynthetic output of diatoms increases, removing more CO2.
b. CO2 absorbed by diatoms is "pumped" to the ocean floor when they die, lowering CO2 levels.
c. Blooms of diatoms kill fish and other consumers, increasing decomposition and raising CO2 levels.
d. Because their glass-like walls are made of silica and not carbon, diatoms do not affect CO2 levels.
e. As the basis of all marine food webs, diatoms perform 50% of the world's photosynthesis and lower CO2.
Answer: b. CO2 absorbed by diatoms is "pumped" to the ocean floor when they die, lowering CO2 levels.
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