Final answer:
Carbon moves through a food chain as part of the carbon cycle when a cow (consumer) eats grass (producer) and then metabolizes it, releasing carbon dioxide back into the atmosphere through respiration.
Step-by-step explanation:
An example of how carbon moves through a food chain as part of the carbon cycle involves a series of transfers between producers and consumers. When a cow, which is a primary consumer, consumes grass, it is obtaining organic molecules such as glucose, which were originally synthesized by the plant via photosynthesis. As the cow digests and metabolizes the grass, it breaks down these carbon-containing organic molecules for energy, resulting in the production of carbon dioxide (CO2) through the process of respiration. This CO2 is then released back into the atmosphere, making it available for the plant to reuse in photosynthesis, completing this part of the cycle.
Furthermore, when organisms like the cow die, decomposers break down their bodies, releasing carbon back into the environment in the form of CO2. Human activities, particularly the burning of fossil fuels, also impact the carbon cycle by releasing significant amounts of CO2 into the atmosphere, contributing to climate change and potentially altering the carbon supply in food chains.