The cells of an embryo are genetically identical.
explain how these genetically identical cells are produced.

An embryo undergoes a process called mitosis to produce identical cells. This is the process by which everything is the cell in duplicated and then the cell splits in half, turning it into two cells with identical parts instead of once cell with two of each part. Then this happens in each of the two new ones and so on, producing identical cells each time. 

Digestion because it removes waste