How confident do you feel about how carbon cycles through the Earth?

Carbon in carbon dioxide that enters a tree for photosynthesis is the same as the carbon in glucose (C6H12O6) produced from photosynthesis.

If I asked you what processes can cycle carbon through the atmosphere and biosphere, how confidently could you answer?

What process removes carbon from CO2 gas and uses it to create glucose (C6H12O6)?

The largest amount of carbon is stored where on Earth

What processes release carbon into the atmosphere as a molecule of CO2 gas?

How much work do you feel is needed before you feel very confident about "how carbon cycles through the Earth's spheres?"