Cleavage is the division of cells in the early embryo.
In the presence of small concentration of yolk,the cleavage is Holoblastic.(complete cleavage,which means the whole cell is divided)
In the presence of large amount of yolk in the egg cell,the cleavage is Meroblastic(partial cleavage)
The cleave in mammals is referred as simple holoblastic because cleavage division divides the cell completely.