Here's why:
* Energy Conversion Efficiency: No energy conversion process is 100% efficient. Some energy is always lost as heat during the transfer from one form to another. This is a fundamental principle of thermodynamics.
* Photosynthesis: Plants capture light energy and convert it into chemical energy stored in glucose. However, not all light energy is captured, and some energy is released as heat during the chemical reactions.
* Cellular Respiration: Organisms break down glucose to release its stored energy for cellular processes. Again, not all energy is captured, and some is released as heat.
This loss of energy as heat is why living organisms need to constantly replenish their energy stores through processes like eating or photosynthesis.
