[Campbell Biology P.706] If a plant forms mycorrhizal associations, where might carbon, whic... | Practice Question

If a plant forms mycorrhizal associations, where might carbon, which enters the plant's stomata as CO2 during photosynthesis, eventually be deposited?

  • A: Solely in the plant, as the fungus is parasitic and only extracts nutrients.
  • B: Solely in the fungus, as the plant transports all its fixed carbon to the symbiont.
  • C: In both the plant and the fungus, as the plant provides carbohydrates to the fungus in exchange for other nutrients.
  • D: The carbon remains as CO2 within the stomata, not being deposited anywhere.

Explanation

In a mycorrhizal mutualism, plants perform photosynthesis, fixing atmospheric CO2 into carbohydrates. A significant portion of these carbohydrates is then transported to the fungal symbiont, providing it with the necessary carbon for its growth and metabolism, while the fungus in return helps the plant absorb water and mineral nutrients from the soil. Therefore, carbon is deposited in both organisms.