For example, the World Health Organization recommends keeping added sugar intake to 10% of total calories. For the average 2000 calorie-diet that's a maximum of 50 grams. The American Heart Association recommends 6 teaspoons of sugar for women and 9 for men (1 teaspoon of sugar has about 4g of sugar).
In developmental biology, cellular differentiation is the process by which a less specialized cell becomes a more specialized cell type. Different tissues have different kinds of cells.
Meristem is a region of plant tissue consisting of undifferentiated or incompletely differentiated cells (meristematic cells) that are capable of cell division and growth and from which new cells are formed. Differentiated plant cells generally cannot divide or produce cells of a different type.