Blastomeres are the nearly identical cells produced by early cleavages during the development of an embryo. Here's why:

* Early Cleavages: The first few cell divisions in an embryo are called cleavages. These divisions happen rapidly and without significant growth, meaning the cells get smaller with each division.

* Identical Cells: The blastomeres initially have very similar genetic material and potential. They are essentially clones of the original fertilized egg.

* Later Differentiation: As development progresses, blastomeres will start to differentiate, taking on different roles and forming the various tissues and organs of the body.

Let me know if you have any other questions about embryonic development!