What key molecule is formed during both photosynthesis and respiration that is critical for energy transfer?

Adenosine triphosphate (ATP) is the key molecule formed during both photosynthesis and respiration that is critical for energy transfer. In photosynthesis, ATP is generated during the light-dependent reactions when sunlight is absorbed by chlorophyll, leading to the production of energy-rich molecules. This ATP is then utilized in the Calvin cycle to help convert carbon dioxide into glucose.

Similarly, in cellular respiration, ATP is produced through processes such as glycolysis, the Krebs cycle, and oxidative phosphorylation. During respiration, glucose is broken down, releasing energy that is captured in the form of ATP, which is then used to power various cellular functions.

ATP serves as the primary energy currency of the cell, allowing for the quick transfer of energy to where it is needed, making it essential for both metabolic processes in plants and animals. This highlights its central role in energy transfer within living organisms.