Girasol definition, an opal that reflects light in a bright luminous glow. See more.
Pheophytin or phaeophytin (abbreviated Pheo) is a chemical compound that serves as the first electron carrier intermediate in the electron transfer pathway of Photosystem II (PS II) in plants, and the photosynthetic reaction center (RC P870) found in purple bacteria.
Overview. The adrenal glands produce the hormone norepinephrine, a potent form of the âfight or flightâ hormone epinephrine. Tumors of the adrenal glands called pheochromocytomas produce abnormally high levels of norepinephrine. The majority of pheochromocytomas are noncancerous.