Melanin has many biological functions, including colouring the skin and hairs or feathers, strengthening plant cell walls and insect cuticle, absorbing light (and so providing photoreceptor shieldlng, thermoregulation, photoprotectlon), and it is an important free radical sink.
Medical Definition of autistic disorder. : autism Autistic disorder is classic autism, one of the more severe disorders on the spectrum. Persons with autistic disorder have substantial impairment in social skills, verbal communication, and cognitive and behavioral flexibility.âIsabelle Rapin , The New England Journal of Medicine, 1 Aug. 2002.
Bipolar disorder is a mental illness marked by extreme mood swings from highs to lows and vice versa. Each of these extreme episodes can last hours, days, weeks, or months. The mood swings may even become mixed, so you might feel elated and depressed at the same time. Bipolar disorder can be hard to diagnose, but there are warning signs you can look for. Keep reading to learn more.