Hereditary diseases are passed from one generation to another through genetic inheritance, which involves changes or mutations in genes that parents pass down to their children. These diseases can be inherited via different patterns including autosomal dominant, autosomal recessive, X-linked dominant, and X-linked recessive inheritance. In autosomal dominant inheritance, the disease can occur if just one copy of a mutated gene is inherited from either parent, giving each child a 50% chance of inheriting the disease. In autosomal recessive inheritance, a person must inherit two copies of the mutated gene (one from each parent) to be affected, while the parents usually carry one copy each but do not show symptoms themselves. X-linked inheritance involves genes on the X chromosome, with males commonly being affected by recessive disorders since they have one X chromosome, while females have two copies and usually need mutations in both for the disease to manifest. There is also mitochondrial inheritance, where genetic material is passed only from the mother through mitochondria. Overall, the passing of hereditary diseases is determined by whether the gene mutations are dominant or recessive and whether they are located on autosomes or sex chromosomes, influencing the likelihood and pattern of disease appearance across generations.