Final answer:
The first law of thermodynamics is observed in a prairie ecosystem through the flow of energy between organisms and their environment.
Step-by-step explanation:
The first law of thermodynamics states that energy cannot be created or destroyed, only transferred or transformed. In a prairie ecosystem, this law is observed through the energy flow between different organisms and their environment.
For example, let's consider a food chain in a prairie ecosystem. The grass is the primary producer that converts solar energy into chemical energy through photosynthesis. The grass is then consumed by herbivores, such as rabbits, which obtain this energy. The rabbits, in turn, are eaten by predators like hawks, and the energy is transferred up the food chain.
This energy transfer and transformation follow the first law of thermodynamics, as the energy is conserved and continually passed on from one organism to another, ultimately providing energy for life processes within the prairie ecosystem.