ANTB15H3 Lecture Notes - Wild Type, Rickets, Osteomalacia
Document Summary
Food value: lactose aspect of fresh milk valuable source of nutrition. Water content: milk provides extra fluid and is a water source (particularly important in arid regions, e. g. , desert nomads. Dietary variation via the animal milked: not directly interchangeable. All are mammals; all have lactose component, but in varying quantities. Unusual about human"s source of milk: high lactose. 20th century: the problem addressed through diet supplementation - vitamin d added to milk (ok as long as you are lactose tolerant . This supplement was added in the 1900s. Single dominant mutation with high penetrance (high proportion of those with the mutation showing signs/symptoms of lactase persistence) Penetrance: you have the gene, but you don"t express it. Inability to break down lactose, the sugar found in dairy products (milk) Inability stems from lack of lactase an enzyme produced by cells in the small intestine.
