This lesson provides a concise review of genetic terminology, deoxyribonucleic acid (DNA), ribonucleic acid (RNA), and chromosome structure and function. It covers the processes for deoxyribonucleic acid replication, transcription, translation, and protein synthesis. It also describes mutations, chromosomal aberrations, and selected associated diseases. The lesson defines elements of formal genetics, including phenotype, genotype, dominance, and recessiveness. In addition, it describes the transmission of genetic diseases and modes of inheritance, including autosomal dominant, autosomal recessive, and X-linked inheritance, and gives examples of representative diseases.