Through which metabolic process does carbon enter the food web?

Define photosynthesis: Photosynthesis is the metabolic process by which autotrophic organisms (like plants and algae) use sunlight, water, and carbon dioxide to produce glucose (C₆H₁₂O₆) and oxygen (O₂). The chemical equation for photosynthesis is: $6_{\mathrm{CO}}+6_H\to C_{6_H}$

Compare other processes: Fermentation, cellular respiration, and glycolysis are metabolic processes that occur in organisms to break down organic molecules for energy. These processes do not introduce carbon into the food web; instead, they utilize carbon already present in organic molecules.