Quick Answer. An experimental variable is something that a scientist changes during the course of an experiment. It is distinguished from a controlled variable, which could theoretically change, but the scientists keep constant. Continue Reading.
While you were pregnant, your baby developed tooth buds, the foundation for baby teeth (also called milk teeth). Very rarely, a baby is born with a tooth or two, or grows a tooth in the first few weeks of life. But the vast majority of babies sprout their first tooth sometime between 4 and 7 months old.
Children usually start losing their baby teeth from around six years of age. From 6-12 years, children have a mixture of adult and baby teeth. The baby teeth at the back are replaced around 10-12 years of age. By this age, most children have all their adult teeth except for the third molars (wisdom teeth).