Green plants are the first living organism in a food chain. where do plants get the energy that they pass along to the primary consumers in their food chains? a. from secondary consumers b. from the sun c. from other plants d. from decomposersgreen plants are the first living organism in a food chain. where do plants get the energy that they pass along to the primary consumers in their food chains? a. from secondary consumers b. from the sun c. from other plants d. from decomposers