The process by which plants lose water is called transpiration. This physiological process occurs primarily through small openings in the leaves called stomata. As water evaporates from the surface of the leaves, it creates a negative pressure that helps draw more water and nutrients up from the roots through the plant's vascular system. Transpiration is essential for plant health and growth, as it aids in nutrient absorption and helps regulate temperature. Additionally, the water vapor released during transpiration contributes to the atmospheric moisture, playing a vital role in the ecosystem.