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.
Definition of Autism Spectrum Disorder. The definition of Autism and Autism Spectrum Disorder (ASD) is provided by the Diagnostic and Statistical manual of Mental Disorders (DSM-IV).Children with autism are less able to interact with the world as other children do.Typically they have deficits in three key areas: 1  Verbal and non-verbal Communication.efinition of Autism Spectrum Disorder. The definition of Autism and Autism Spectrum Disorder (ASD) is provided by the Diagnostic and Statistical manual of Mental Disorders (DSM-IV).