As an aside, the sun even powers our human activities via fossil fuels which were are the byproducts of long-dead plants. B. Plants are solar energy conversion factories. C. Plants and animals are powered by the products of photosynthesis. D. Life and Thermodynamics. They produce about 200 billion tons carbon fixed annually.
Consumers convert the chemical energy in plants to additional forms of chemical energy.
Gross primary productivity refers to the total amount of photosynthesis by plants. Secondary productivity - amount of energy in consumers. The energy is lost primarily as heat. This is caused by the energy loss at each stage. Energy pyramid can never be inverted, others can.