Which process describes the evaporation of water from leaf surfaces followed by loss through stomata?

Which process describes the evaporation of water from leaf surfaces followed by loss through stomata?

• A. Transpiration
• B. Evaporation
• C. Translocation
• D. Respiration

Answer: (A)

Transpiration describes how water moves up from the roots through the plant, reaches the leaves, and is lost as water vapor from leaf surfaces through the stomata. Inside the leaf, water evaporates from moist cell walls and diffuses into air spaces, then exits via the stomatal openings. This not only accounts for water loss but also helps pull more water up the xylem from the roots, thanks to cohesion and tension in the water column. Stomata openings are tied to gas exchange for photosynthesis, so evaporation through stomata is a combined path for water loss and leaf cooling. The other terms don’t fit this specific pathway: evaporation is just liquid turning into vapor without naming the plant’s leaf pathways; translocation is the movement of sugars in the phloem; respiration is how cells release energy from glucose.

Transpiration describes how water moves up from the roots through the plant, reaches the leaves, and is lost as water vapor from leaf surfaces through the stomata. Inside the leaf, water evaporates from moist cell walls and diffuses into air spaces, then exits via the stomatal openings. This not only accounts for water loss but also helps pull more water up the xylem from the roots, thanks to cohesion and tension in the water column. Stomata openings are tied to gas exchange for photosynthesis, so evaporation through stomata is a combined path for water loss and leaf cooling. The other terms don’t fit this specific pathway: evaporation is just liquid turning into vapor without naming the plant’s leaf pathways; translocation is the movement of sugars in the phloem; respiration is how cells release energy from glucose.