The introns of protein-encoding nuclear genes of higher eukaryotes almost invariably begin (5') with GT and end (3') with AG. In addition, the 3'subterminal A in the “TACTAAC box” is completely conserved; this A is involved in bond formation during intron excision.
Inside the cells of plants, algae, and photosynthetic bacteria, chlorophyll, and enzymes use the light energy to rearrange the atoms of the reactants to form the products, molecules of glucose and oxygen gas.
