Question

The carbon that plants need for photosynthesis comes from
A.
carbon dioxide gas in the atmosphere.
B.
carbon molecules dissolved in water.
C.
carbon molecules that the plant produces.
D.
carbon atoms from the breakdown of food.The carbon that plants need for photosynthesis comes from
A.
carbon dioxide gas in the atmosphere.
B.
carbon molecules dissolved in water.
C.
carbon molecules that the plant produces.
D.
carbon atoms from the breakdown of food.The carbon that plants need for photosynthesis comes from
A.
carbon dioxide gas in the atmosphere.
B.
carbon molecules dissolved in water.
C.
carbon molecules that the plant produces.
D.
carbon atoms from the breakdown of food.

Answer 1

A. carbon dioxide gas in the atmosphere.

Plants fix CO2 from the air (or dissolved CO2/bicarbonate in water for aquatic plants) during photosynthesis, using the carbon to build sugars in the Calvin cycle.