Quantitative information on integrative and cumulative effects can be gained by experiment when whole plants are grown from seed to maturity, and by mathematical simulation of whole plant growth. Fruits are the plant parts most often used in the development of food products. With increasing Carbon dioxide (CO2), the number of plants grown per unit of ground area, the size of each fruit, and the number of fruits per plant may change. Many species have relatively narrow genetic limits on the size of the fruit, but enhancement of the photosynthate supplies in the plant may result in larger fruit, and the plant may be able to support more fruit. Primary effects of CO2 on photosynthesis and transpiration occur via the CO2 concentration gradient and the CO2 effect on stomatal aperture. Several measurements of the effects of doubling CO2 concentration on transpiration itself have been made in chambers with short-term experiments.