What is the primary source of energy that drives the process of transpiration?

• A. The wind
• B. The soil
• C. The sun
• D. The water

Answer: (C)

Transpiration is the process through which water vapor is released from plant leaves into the atmosphere. The primary source of energy driving this process is the sun. Solar energy heats the surface of leaves, causing water to evaporate from tiny openings called stomata. As moisture is lost from the leaves, it creates a vacuum that helps pull more water upward from the roots through the plant's vascular system. This movement not only supports transpiration but also aids in nutrient transport within the plant. While factors like wind can influence the rate of transpiration by facilitating evaporation and soil quality can impact water availability, it is the sun's energy that fundamentally powers the entire process.