ABSTRACT
Plants are capable of producing all organic materials required for growth, metabolism, and reproduction from very simple inorganic molecules obtained from the atmosphere and the soil. Using light energy trapped by chlorophyll in the process of photosynthesis, these inorganic molecules (principally CO2, phosphate, and nitrate or ammonia) are incorporated within the chloroplasts of mature leaves in a number of relatively simple biomolecules (e.g., triose phosphate, amino acids), which are then used elsewhere in the cell for respiration or for the construction of the more complex biomolecules (e.g., complex saccharides, proteins, nucleic acids) required for growth and metabolism. In agronomic crop species, the incorporation of fixed carbon into carbohydrates is particularly important, for carbohydrate production largely determines the yield of crop plants.
