Stores in the carbon cycle quiz

What percentage of the Earth's atmosphere is made up of carbon dioxide (CO2)?

• 0.04%

• 0.4%

• 4%

• 40%

Answer explanation

The correct percentage of the Earth's atmosphere made up of carbon dioxide (CO2) is 0.04%, as it is a trace gas in the atmosphere.

Which sphere could be described as the living fabric that comprises plants and animals?

• The atmosphere

• The biosphere

• The cryosphere

• The lithosphere

Answer explanation

The biosphere is the correct choice as it refers to the living fabric that comprises plants and animals on Earth.

Approximately how many times the amount of carbon contained in the atmosphere is stored in the cryosphere?

• 0.5 times

• 1.5 times

• 2.5 times

• 3.5 times

Answer explanation

The correct answer is 2.5 times because the amount of carbon in the cryosphere is approximately 2.5 times the amount in the atmosphere.

What is the largest store of carbon on Earth?

• The atmosphere

• The biosphere

• The cryosphere

• The lithosphere

Answer explanation

The largest store of carbon on Earth is the lithosphere, which includes rocks, soil, and sediments where carbon is stored for long periods of time.

Which sphere covers 71% of the Earth's surface and contains the second largest quantity of carbon?

• The atmosphere

• The biosphere

• The lithosphere

• The hydrosphere

Answer explanation

The hydrosphere covers 71% of the Earth's surface and contains the second largest quantity of carbon, making it the correct choice.

Carbon in the soil layer is present in which forms?

Answer explanation

• - gaseous, solid and liquid forms (in both organic and non-organic forms)

• - gaseous as CO2 sored in air bubbles

• - Solid as carbon in weathered sedimentary rock and decomposing plant and animal matter

• - liquid as soluble calcium bicarbonate ions from chemical weathering and rainwater

which of these is not a form of carbon in the cryosphere

• organic carbon in the permafrost layer

• weathered sedimentary sediment entrained within a glacier

• weathered igneous rock at the bottom of a glacier

• bubbles of CO2 trapped within the ice

describe three forms of carbon found in the hydrosphere

Answer explanation

in gaseous form as dissolved CO2 from atmosphere (non-organic)

in organisms such as plankton, corals, shells (organic)

in seafloor sediments containing CO2 and CH4 (non-organic)

What process is primarily responsible for the transfer of carbon from the atmosphere to the biosphere?

• Photosynthesis

• Respiration

• Decomposition

• Combustion

Which of the following is a significant source of methane, a potent greenhouse gas?

• Volcanic eruptions

• Peat bogs and Wetlands

• UV radiation

• Ocean currents

Answer explanation

Peat bogs and Wetlands are significant sources of methane, a potent greenhouse gas.