Dear student,
Directly or indirectly all the herbivorous, carnivorous, and omnivores depend on autotrophs. The autotrophs form their food through the photosynthesis using carbon dioxide and light. They fix carbon dioxide during the light-independent reactions of photosynthesis Therefore, the autotrophs depend on the carbon dioxide. Hence, the life dependent on the carbon fixation that occurs during the light-independent reactions of photosynthesis.
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