Grade 12

Genetics is the study of heredity and variation of inherited characteristics. Key terms in genetics include genes, which are segments of DNA that carry hereditary information; alleles, which are different forms of the same gene; and genotypes and phenotypes, where genotype is the genetic makeup and phenotype is the physical expression. Modern branches of genetics include cytogenetics, molecular genetics, phylogenetics, developmental genetics, and behavioral genetics. Sexual reproduction occurs through fertilization while asexual reproduction involves copying without fertilization. Genetic diseases can be passed from parent to child through dominant or recessive alleles