One of 16 booklets designed for use in an Open University course on the education of handicapped students in the United Kingdom, this document considers biological factors involved in handicapping conditions. An initial chapter examines the portrayal of disabled persons in drama, literature and film. Genetic involvement (autosomal dominant inheritance and recessive inheritance) is considered. Educational implications of children with hearing impairments and epilepsy as well as children whose physical condition requires the use of special equipment and personnel are analyzed. Similarly, the implications for children who are categorized according to syndromes such as autism, dyslexia, and hyperactivity are reviewed. The involvement of the medical profession in education is the topic of another section. A conclusion asserts that medicine's role in the education of most children with disabilities should be limited. (CL)