Orange (colour) and absorb mostly greenish-blue light. (See also shades of orange). Other orange pigments include: The orange colour of carrots, pumpkins, sweet potatoes, oranges, and many other fruits and vegetables comes from carotenes, a type of photosynthetic pigment. These pigments convert the light energy that the plants absorb from the sun into chemical energy for the plants' growth. The carotenes themselves take their name from the carrot. Autumn leaves also get their orange colour from carotenes. When the weather turns cold and production of green chlorophyll stops, the orange colour remains. Before the 18th century, carrots from Asia were usually purple,
Photodissociation chlorophyll molecule (P680, where P stands for pigment and 680 for its absorption maximum at 680 nm) in the reaction center of photosystem II via resonance energy transfer. P680 can also directly absorb a photon at a suitable wavelength. Photolysis during photosynthesis occurs in a series of light-driven oxidation events. The energized electron (exciton) of P680 is captured by a primary electron acceptor of the photosynthetic electron transfer chain and thus exits photosystem II. In order to repeat the reaction, the electron in the reaction center needs to be replenished. This occurs by oxidation of water in the case of