Polarized light micrograph of L-serine semi-essential amino acid crystals, critical for the synthesis of the body's proteins, enzymes, muscle tissue, immunoglobulins, and antibodies. It is necessary for specific functions in the central nervous system. Serine is needed for the proper metabolism of fats, fatty acids, cell membranes, and muscle growth. L-Serine plays a role in cell growth and development (cellular proliferation). Altered levels are linked to fibromyalgia, chronic fatigue syndrome, and mental disorders (depression, insomnia, confusion, and anxiety). It is used as a natural moisturizing agent in some cosmetics and skin care products. Field of view size: 1.485 x 2.227 mm (0.0585 x 0.0877 in)