Final answer:
In a terrarium, energy flows from the sun to plants through photosynthesis, from plants to animals through consumption, and from both plants and animals to the environment as heat during cellular respiration.
Step-by-step explanation:
In a sealed terrarium containing a plant and a beetle, energy and nutrients are transferred and transformed via photosynthesis and cellular respiration. Photosynthesis is the process by which plants use light energy from the sun to convert carbon dioxide and water into chemical energy stored in glucose. This transformation can be represented by arrows from the sun (light energy) to the plant (chemical energy in glucose).
Cellular respiration is the process by which both plants and animals break down glucose to harness the chemical energy as ATP, releasing heat in the process. Animals, like the beetle in the terrarium, consume plants or other organisms to obtain glucose. The energy stored in glucose flows to the beetle as it eats the plant, and further, when the beetle undergoes cellular respiration, some of the energy is lost as heat.