Blastospheres are hollow balls of cells that form during the early stages of embryonic development. When discussing embryos and stem cells, the word blastosphere is often used. However, there are several synonyms for this term that can be used interchangeably. A popular synonym is "blastula," which is a term used to describe an early-stage embryo that has developed into a hollow sphere with a fluid-filled cavity. Another synonym for blastospheres is "blastoderm," which refers to a thin layer of cells that covers the yolk of an egg. Other terms used to describe this stage of embryonic development include "gastrula" and "morula." Regardless of the terminology used, the formation of a blastosphere is a crucial step in the growth of a developing organism.