Question

This is a typical grassland food web. It is also a small picture of an important cycle on Earth: the carbon cycle. Describe how the carbon gets into this food web.

a. Bacteria and fungi, the decomposers, recycle carbon from dead organisms.
b. Carbon is found in the grass and is passed from one level to the next in this food web.
c. All living things give off carbon dioxide as a by-product of respiration and it is released into the atmosphere.
d. Plants use carbon dioxide as a reactant in photosynthesis, to make usable chemical energy in the form of a sugar.

Answer 1

The correct answer would be option D.

In any food web, the inorganic carbon from the atmosphere is incorporated into the organic matter by the process of photosynthesis.

Autotrophs perform photosynthesis and fix carbon obtained from carbon dioxide into the glucose or organic matter with the help of chlorophyll and in the presence of sunlight.

6 CO₂ + 6 H₂O → C₆H₁₂O₆ + 6 O₂

Answer 2

The correct answer is letter d. Plants use carbon dioxide as a reactant in photosynthesis, to make usable chemical energy in the form of a sugar. In a typical grassland foodweb, carbon is used by plants (carbon dioxide) to create food for themselves.