Ocean Equilibria

How does carbon dioxide primarily enter the ocean?

• through ocean currents

• via the carbonate pump

• by air-sea surface exchange

• through biological respiration

What percentage of the world's oxygen is estimated to be produced by phytoplankton?

• less than 10%

• approximately 25%

• around 50%

• over 75%

What allows organisms to move carbon compounds through marine food webs?

• photosynthesis

• consumption

• thermohaline circulation

• upwelling currents

Which process in the ocean is responsible for converting dissolved carbon dioxide into carbohydrates?

• consumption

• respiration

• photosynthesis

• death and decomposition

Which "pump" moves carbon compunds around the ocean through upwellings, downwellings and currents?

• physical carbon pump

• biological carbon pump

• carbonate pump

What is the main by-product of photosynthesis in the ocean?

• carbon dioxide

• oxygen

• carbohydrates

• calcium carbonate

Which process involves thebreakdown of carbohydrates back into carbon dioxide?

• photosynthesis

• consumption

• respiration

• death and decomposition

How long can carbon compunds stay in slow-moving deep ocean currents before returning to the surface?

• a few years

• tens of years

• thousands of years

• millions of years

What happens to the organic matter of dead organisms in the ocean?

• It accumulates at the ocean surface

• It remains suspended in the water column indefinitely

• it is broken down by bacteria into simpler compounds

• it is converted directly into calcium carbonate

As increasing water temperature due to climate change strengthens the thermocline, what will happen to the ability of the ocean to sequester carbon?

• It will be reduced because of an increase in thermohaline circulation

• It will be reduced because of a decrease in vertical mixing in the ocean

• It will be increased because of an increase in photosynthesis

• It will be increased because of an increase in decomposition rate