Question

The carbon atoms in the cellulose of a wood log originally came from ________ absorbed by the plant.

Answer 1

Carbon dioxide

Step-by-step explanation:

During photosynthesis, plants incorporate their only source of carbon through carbon dioxide (CO2) and together with water (H2O) and sunlight they synthesize glucose and oxygen.

6 CO2 + 6 H2O → C6H12O6 + 6 O2

Cellulose is a structural polymer formed by β-glucose (C6H10O5)n monomers arranged in an unbranched manner. This is synthesized in plants by the cellulose synthase complex (CSC). To do this the plant uses the glucose that was synthesized during photosynthesis.

So the source of the carbon atoms in cellulose came from the CO2.

Answer 2

It came from carbon dioxide, a colorless and odorless gas and has a density of more or less 60% more than the density of the air. The chemical formula for carbon dioxide is CO2. In photosynthesis process, the plants utilize the energy provided by the sun and convert it to CO2.